Koi no Furi Shite Kimi wo Yobu

I shouldn't fall for this guy.

Yui, a college student, is determined to get revenge on Ren, his sister's ex, who once made her cry. His plan? Make Ren fall for him and then break his heart, so he can feel the same pain he caused his sister. Dating Ren, who never turns anyone down, isn't difficult, but for Yui, a complete beginner in love, the real challenge begins afterward. Between kind gestures, playful teasing, and stolen kisses... Yui's heart won't stop racing! From the day he tells Ren, "I want you to love me so much you can't imagine a world without me" he starts receiving special treatment...!?

(Source: Frontier Works, translated)

Note: Includes one extra chapter.