Two couples engage in mutual NTR during a home drinking party!! Sakura-chan is relaxing at her boyfriend's house... but the atmosphere between them is a bit heavy. While Sakura-chan is feeling dissatisfied with her boyfriend's attitude, her best friend Mari-chan calls. Mari-chan and her boyfriend Yuma, who recently started dating, join them for drinks! As the alcohol kicks in, Sakura-chan exposes her boyfriend Haruto's cheating stories, and the romance talk gets heated! Eventually, all four fall asleep... In the quiet room, Haruto starts making a move on Mari-chan... (Actually, Haruto and Mari-chan have had sex before!) Mari resists at first, saying "I can't...", but she gradually gives in... and secretly has sex with Haruto in the bathroom!! Yuma notices something is off, but Sakura-chan suddenly kisses him, saying "They're definitely doing something over there... let's do it too!" A sudden temptation! In this NTR situation, the perverted Yuma gets rock hard!! Completely knocked out by Sakura's skillful hip grinding in cowgirl position, he gives her a reverse NTR creampie! While Sakura, still not satisfied, continues the cowgirl sex... Mari-chan and Haruto unexpectedly join in!! "Let's do it over here too!" Haruto says, and starts mutual NTR sex with Mari-chan again!!! It develops into a couple-to-couple NTR 4P orgy!! A mix of jealousy and shame!? Constant orgasms push away the complex emotions!! The finale is, of course, a deep creampie from her best friend's boyfriend!!! Even so, Mari and Sakura are still best friends! Creampie buddies! "What do you think? Should we just swap boyfriends? lol"