Aru Koroshiya no Kanwa

Also known as: ある殺し屋の閑話, A Hitman's Idle Tale

by Akari Homine

Towa, the daughter of a company president, feels like her life is in danger after the death of her parents. Following her late father's instructions, she moves into an apartment, but to her surprise, it is in an apartment complex for criminals only! And now she's caught the attention of Skull, the most dangerous assassin in the world...! (Source: MangaPark, translated)