"Hey! Do you know what swapping is? I hear it's popular these days." With that casual comment from Hikari, the after-school classroom suddenly heats up. When Moa replies, "It's that thing where you swap couples, right??", Hikari responds, "You know about it! You're pretty informed." "Have you ever done it?" "No way lol, it's common in erotic videos," they laugh together. Then she continues, "It's where you exchange partners! Go on dates! Have sex!" Moa refuses, saying "What do you want to do? I don't want to~", but Hikari shakes her, "Ew, no, no! You're okay with someone else doing things to you? Don't you love him anymore?" Moa argues back, "I love him! That's why I don't want to do it, lol!" Hikari persuades, "When you date for a long time, it gets stale, right? It's supposed to be a spice to fix that." "Swapping isn't cheating! It's approved! Doesn't it sound fun?" Moa dislikes it, saying "That's the worst! No, no," but Hikari pushes through, "I bet it'll be exciting!" And so, two young couples—Hikari & Moa (18 years old) and their respective boyfriends—exchange partners under the name of swapping and start flirting in a corner of the classroom. The schoolgirls reveal their fresh, youthful bodies with beautiful breasts and big tits, and the orgy in the midst of their youth is like a secret game. While showing each other their sex, the swapped dicks and pussies intertwine. "Your boyfriend's dick feels so good (blush)," says Hikari, her cheeks flushing. "This dick is amazing too... ahh, I'm gonna cum!" Moa moans. Then voices overlap: "No no no... I'm feeling it...!" "Ahh ahh ahh ahh! Sorry, I'm cumming!" and "I'm cumming on another guy's dick! I'm cumming—!" as they both climax simultaneously. In the forbidden place of school, the spice of approved cheating ignites the friend couples—a dense time even allowing creampies echoes through the classroom.