ONE WEEK RULE ( BxB/ KAI ZEN )

Cream is a charming, attractive nineteen years old college student who's popular because of his 1 week rule, he almost dated half of the women's population in their school, having a sweet relationship and ended up on the seventh day of the so called " RELATIONSHIP".
Hindi siya namimili ng mga gugustuhin, weight, height, skin color, age, it doesn't matter on him. Kaya naman maraming babae ang nagkandarapang maging ka-relasyon siya even for a week.
But little did he know, na may isang lalaking magtatapat sa kanya na gusto nitong makarelasyon siya. It's a big joke, knowing Kai Zen Aihara? Ang popular soccer player na basagulero, guwapo, mayaman at higit sa lahat bully na lalaking 'yon ay balak ata siyang pag-tripan? Pero kumasa siya sa hamon nito.
What will happen on their One Week Relationship? Is it possible to love someone as early as 1 week?