Episode 161

Miroku's Past Mistake is the 161st episode of the InuYasha anime.

Summary
Miroku and Sango have vowed to marry once the battle with Naraku is over. However, their relationship is thrown into chaos with the emergence of one of Miroku's past scams. Will the love between them endure and become stronger, or will this encounter bring an end to their relationship? One things for sure: it's Miroku's fault (mostly).

Plot
Inuyasha, Kagome, Miroku and Sango are walking along a trail and Miroku is seemingly upset over getting pick-pocketed by a man. But, instead, he uses his supposed sadness as an excuse to stroke Sango's bottom in a hug. (This is  the first of a few times he's gotten away with groping). Kagome says to Inuyasha and Shippō "What he does, and what he says are complete opposites. As usual." Both sigh in agreement.

Some villagers place a charm on a shrine, praying that the soul will find peace. As they do, the ground shakes and the water roils. As Inuyasha and companions arrive to offer help, one of the villagers recognizes Miroku and asks if he has returned to fulfill his promise and marry his daughter, shocking everyone (including Miroku) since Miroku is engaged to Sango.

In the village, Miroku is unable to recall the promise at first, since he's met many women and pulled many scams over the years. However, when a young lady arrives, he recognizes her. The girl, Shima, used to be sickly and frail. However, Miroku gave her parents medicinal herbs to cure her, though it was, in their words "very expensive medicine"; Miroku laughs nervously. InuYasha and Sango immediately know that "he swindled them." Kagome then asks if Miroku and Shima become "quick friends", but Miroku says he did nothing of the sort; Shima confirm this, explaining Miroku left as soon as he gave her the medicinal herbs. Miroku taunts Kagome for her accusation, but Shima adds that Miroku had asked her to bear his child once she was healed and she actually agreed.

Kagome yells at Miroku, because he was trying to seduce Shima, especially since she was only a girl; Sango whacks Hiraikotsu against Miroku's head, sarcastically saying "Oh, it's okay. After all, it's a thing of the past." Shima claims that the medicine as well as her promise to Miroku is what kept her going. These events soon cause a great strain on Miroku and Sango's relationship as Sango becomes further and further upset now fully taking in Miroku's womanizing past. However, Inuyasha butts in, reminding everyone that they're there because of the demonic presence at the lake.

The house begins shaking again, making Shima cling to Miroku, saying she's scared. Miroku can only think to himself "So am I, but for whole other reason!" as Sango glares at his back. Inquiring into what is making the quakes, the companions learn that the water demon who lives in the shrine, the Master of the Lake, has claimed Shima as his bride and refuses to give her up. Shima explains she tried informing the Master of the Lake that she is already engaged. Nervous, Miroku questions who it could be. Kagome and Sango yell that it's him. Putting the awkward moment aside, Miroku vows to make sure Shima doesn't have to marry the demon. However, Shima's father takes this as accepting the marriage and begins preparations, much to Miroku's dismay.

That night, everyone but Miroku is outside on guard duty. Shippō wonders why Miroku is the only one inside, making Kagome explain that Miroku is trying to explain everything. This confuses Shippō, who doesn't understand relationships well; he wonders if Miroku's turning down Shima, only for Kagome to say "He'd better; he's promised to marry Sango." Inuyasha asks Sango, who is upset, if she can trust Miroku to be alone with Shima, quoting "Only a fool refuses a woman who offers herself." Furious, Kagome tells him to sit; she berates him for saying something so dirty, asking him where he even heard it, and questions if he actually took Sango's feelings into account. Sango is left thinking that she was placed second in importance.

Inside the house, Miroku wonders why the Master of the Lake would give up if Shima was wed, learning the demon wants a virgin as his bride; if a marriage ceremony was held, the Master of the Lake would give up on Shima. Miroku finds it oddly honorable of a demon to do so; Shima begs him to marry her as soon as possible. Shima's father makes the same quote as Inuyasha, making Miroku laugh uncomfortably. At that moment, what appears to be an exaggeration of an angry Sango appears before them, calling Miroku's name. However, it's actually Shippō, who wished to convey Sango's feelings to Miroku. Sango enters and takes Shippō back outside, but not before giving Miroku a look and thinking "Drop dead, idiot". Stunned, Miroku immediately knows what Sango was thinking, even guessing the exact words. They question Miroku as to who Sango is. Right as he's about to explain, the ground begins shaking.

Outside, the ground bursts at the gate, revealing a very short and rather ugly water demon dressed in formal attire, bringing a cart of gifts with him. InuYasha, Kagome, Shippō & Sango are unimpressed, having been expecting something a bit more frightening. The Lake Master greets Shima delightedly and blows her kisses, horrifying her. When Shima continues to hide behind Miroku, the Master of the Lake wonders why she is refusing as he was promised her hand in marriage; everyone is confused.

Shima's father explains that he had used water from the lake in order to boil the medicinal herbs Miroku sold him. While there, he also prayed at the shrine, promising the Master of the Lake anything in return for his daughter's good health; he didn't know his prayers were actually being listened to. Shima then confesses to the Master of the Lake, as well to her parents and the group, that she is not a virgin. She insists that she had slept with Miroku and gave her virginity to him (causing Sango to be silently enraged) and is thus unfit as a bride; Miroku is just as stunned, as he would have remembered something like that. The Master of the Lake, furious and hurt that he had been lied to, transforms into a gigantic catfish and attacks the house. When Miroku calls for Sango's help in bringing down the demon, Sango coldly refuses. Sango rejects Miroku, saying that she doesn't think things will work out between them after all, while Inuyasha attacks and easily defeats the demon which she seems to be unfazed by, stunning Miroku that she is ending their engagement.

Miroku tries to explain things to her asking if he could even give his side of the story, but Sango runs off clearly distressed and Miroku is left gut-wrenched that she doesn't trust him. Miroku soon reveals to Inuyasha, Kagome and Shippō that he had actually been falsely accused of the things he had supposedly done with Shima and that his heart "was focused on one person and one person alone." While they are distracted, the Lake Master kidnaps Shima.

Elsewhere, Sango is sitting at the lake, sadly thinking that Miroku won't follow after her. She then notices the Lake Master arriving with Shima, saying he'll take her as his wife even through she's not a virgin; Shima repeats her earlier claim, with the words stinging Sango. However, the Lake Master says he will forgive her mistake and drags her deep into the lake Sango rescues Shima from him, but is caught by the demon in the process. When the demon gloats that he shall keep Sango as his mistress, Miroku leaps into the lake after them declaring that no one will go after "his woman," clearly shocking Sango. Miroku then uses his Wind Tunnel to drain the lake; without any water, the Master is left flopping around until Miroku slams his staff on sutras placed on its head; it reverts to its, ugly formal attire form. Miroku whacks him on the head, telling the "catfish" to stay away from his woman; the Master is shocked to find Sango is another of Miroku's "women" and apologizes. Miroku gives the Master another whack to head and asks Sango is she's okay.

Sango walks away from Miroku, seemingly still upset. Miroku chases after her, but as she continues walking away, she smiles to herself. Miroku sees and smiles as he continues chasing after her as the others watch from nearby. As the circle the dried lake, they repeatedly step on the Master's bruised head, pushing him further into the ground. Inuyasha is left annoyed that they didn't need him. Shima watches Miroku chase Sango, saying they make a great pair.

Once everyone is out fo the lake, Shima reveals that she lied about sleeping with Miroku ("I guess I just didn't want to wed the catfish"). Miroku explains it was the only thing Shima could think of the dissuade the Master at the time, saying it was his foolish belief that Sango would trust him despite his womanizing past; he asks for forgiveness, but Sango says the same thing. Kagome says Sango has a big heart, but Shippō notes sometimes Sango's heart is bigger than Kagome's.

As everyone walks away, the order they usually are in is reversed; Miroku and Sango are in front. Every time Miroku looks at Sango, she blushes and turns away. Thinking to himself, Shippō asks Miroku why simply didn't just explain everything sooner to clear up the misunderstanding - "Guess it took you a long time to remember." This comment shocks Miroku in place. Inuyasha tells Shippō - "Bulls-eye on that one." Grabbing Miroku by the collar, Sango glares and demands to know if Shippō is right. Sweating profusely because of a possible beating, Miroku says "Well, it was so long ago..."