Infant

Akago is baby yokai and the seventh detachment of Naraku. Akago is quite unique in that he poessess Naraku's heart, meaning that no matter how much physical damage Naraku takes he cannot be killed. Of course the reverse is true meaning if he dies then Naraku will die as well. In the anime the baby plays a small role and is often hidden by Kanna in order to protect Naraku's heart. In the manga upone realizing his importance to Naraku the baby rebells against Naraku and imbarks on a quest to replace him, the anime ends before it reaches this point. He also acts as Moryomaru's soul/heart and use his body to try to over throw Naraku.

Histroy
After Naraku was nearly killed by InuYasha and Sesshomaru he ran away to Mount Hakurei. While there he shedes all Onigumo's love/lust for Kikyo from his heart into lumps of flesh. Naraku does not stop there, he also removes his heart and puts it inside one of his detachments, the baby. After Mount Hakurei was destroyed the baby is given to Kagura for her looks aftet, the two of them escape Hakurei togther. When Naraku killed Kikyo(or so he believed) on Mt. Hakurei the baby tells Kagura about the act, but appears to be delighted by it. The baby's first mission for Naraku was to take control of Kagome, so that Naraku could use her abiltiy to see jewel shards to find the last fragment.

A plot that ivolves luring InuYasha away from the group by spreading false rumors of Kikyo being alive, the plot succeeds leaving the rest of the group to be abducted by guards under the orders from their lady(who is being controlled by the baby). When Kagome is brought to the lady the baby and Kagura reveal themselves. He using Kagome's jealousy of Kikyo and inseurities to bring out the darkness of her heart so that he can take control of her mind. He almost succeeds, but Kagome realizes that her feelings are normal and is able to overcome the baby's control. InuYasha, Miroku, and Sango come to Kagome's rescue and question the baby about being Naraku's heart. He reveals that he is indeed Naraku's human heart, but he does not have Onigumo's lust/love for Kikyo. InuYasha in anger of what the baby did to Kagome unleashes the Kaze no Kizu, but the baby creates a barrier around himself, Kagura, and Kanna, and reverses the attack back on the group. He leaves with Kanna and Kagura, but tells InuYasha that with only a few shards left Naraku will not give up on using Kagome to find them.