Seigi, a martial arts trained middle schooler, often feels driven to protect the weaker people around him. One day, he defends a homeless man against some punks, and the man gives him a strange tattoo on his palm in return. The tattoo is a secret weapon produced in the arms race between America and the Serinistan Kingdom. Seigi finds himself in over his head when a powerful girl, using the same secret weapon, violently pursues him in order to retrieve it. His skill at martial arts may not be enough to keep him alive, but will he be able to learn how to trigger the power of his tattoo in time? (Source: MU)

Saikin, Imouto no Yousu ga Chotto Okashiinda ga. follows a family just starting to rebuild. When they marry, Mr. and Mrs. Kanzaki bring a teenage son and daughter along for the ride. But high school freshman Mitsuki Kanzaki is less than thrilled. Stinging from a history of absent and abusive father figures, she is slow to accept her stepfather and stepbrother. But after an accident lands Mitsuki in the hospital, she finds herself possessed by the ghost of Hiyori Kotobuki, a girl her age who was deeply in love with Mitsuki's stepbrother Yuuya. Hiyori cannot pass on to her final reward because of her unrequited love for Yuuya, meaning she's got to consummate it... in Mitsuki's body?! Now, Mitsuki's life depends on getting Hiyori to Heaven. But will she get used to sharing herself with a pushy, amorous ghost? Can she overcome her distrust of her new family? Can she bring herself to fulfill Hiyori's feelings for Yuuya? And might she be hiding some feelings of her own?

This OVA is divided into two parts. First one is about Torii Shoutarou following his younger sister on a date. Second one is about Christmas Eve, which Mitsuki, Yuuya and their friends spend at Kanzaki's house. Bundled with the limited-edition volume 7 of the manga. (Source: AniDB)

Hiiragi Kyouichirou is a boy who travels from his provincial town to Tokyo to attend university. He carries with him his family's sword to protect himself. When he arrives in Tokyo, he becomes swept up in a plot by the Imperial army. (Source: ANN)