Amaku Shibirete Nukenai, Ani no Toge: Shun-chan, Daisuki desu...

It's nice to be living with the man you love... even if he happens to be your stepbrother. Shun and Ruri have been stepsiblings since their parents remarried when they were kids. Now they both attend the same college, and share a secret that nobody else can know! In comparison to reserved and plain Ruri, Shun has always been popular with both guys and girls. He's rumored to being gentle in bed, but when it comes to Ruri, he can't stop his possessive streak from getting the best of him...!

(Source: Renta!)