Koneko ♂ ga Matteru node Kaerimasu.

Stressed to the max at work, Miyako thought adopting a cat would help. But nothing worked out and she was going home empty-handed when she found a kid passed out in the snow wearing a cat-ear parka. Miyako rushed the kid home and cleaned him up to find a beautiful little boy, who promptly threatened her to let him stay or else he'll call the police! A cute bishonen x OL roommate story begins! Note: Chapter count includes 18 main chapters, 12 omake chapters, and 3 volume-bonus chapters.