Kairaku no Houteishiki: LEVEL-C

Mizuki is a popular male fashion model with a promising future.​ When the mysterious Haruno sees him,​ She wants to make him the centerpiece for her company's latest promotion.​ To lure Mizuki in,​ she calls on the talents of her twin brother,​ Kazuomi.​ He is quick to seduce the young super-model,​ but things soon escalate beyond business as usual.​ As Kazuomi's feelings run away with him,​ it looks like true love for him and Mizuki.​
(Source: Kitty Media)