The Enchanted Sword Masamune- Break the Soul Possession: A Heart Sings in the Rain?
Tsubaki agrees to take a mission to hunt down Masamune before it becomes a corrupt Demon Sword. She takes Black Star along (of course) only to have him clash with the villagers who have suffered a number of attacks from the Star Clan (a family of assassins that Black Star is descended from).
Black Star admits that calling the Star Clan “assassins” is something of a misnomer since they got bored with warmongering and started hunting human souls for power, like the kishin. They were wiped out by Lord Death and the Academy 13 years ago. Black Star. a baby at the time, was brought to the Academy because he was still pure. While he struggles to be a successful meister the people he encounters only see a small guy who is a member of the Star Clan, and thus someone to punish for their pain.
Meanwhile the enchanted sword possesses people based on anger and takes them over to cause more fear and pain to feed on. Back in the town one of the villagers falls prey because of Black Star’s presence, leaving Tsubaki and Black Star to face down against the weapon in its power, instead of at a weak point as they hoped. And there’s still something that Tsubaki isn’t telling Black Star about her connection to the sword.
This episode really shines in its fleshing out of characters. While mostly Black Star is portrayed as an egomaniac and idiot, you’re told there’s a lot behind it based only on Tsubaki’s attachment and protection of him. However in this episode the wall is dropped and you see what’s inside Black Star and why Tsubaki feels so attuned to him.