My Younger Boyfriend Is Being Unreasonable

Lise moves into a two-bedroom apartment she's supposed to share with her boyfriend, except he breaks up with her without warning. Furthermore, her ex brings an attractive guy, Subaru, to the apartment and asks her to look after him! Subaru's younger, but he can cook and he listens to all her problems. He tells her that he wants to make her feel better because she gives too much of her time and energy to both her work and her ex... Lise indulges Subaru's request. She melts under his lips that carefully travel her body and his soft touches... The next day, she gets a phone call from her ex warning her about Subaru... Who is this guy?!