Jogakkou de Otoko Hitori na node Kousoku de Seiyoku no Hakeguchi ni Sareru Nichijou – Chapter 4 Scene 2

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Chapter Link (Pages 51-64)
Rating: 4

The MC has a foursome with Aoi, Lilliana and Midori.

On Pages 54 & 57, Aoi and Midori are briefly shown having lesbian sex in the background while the MC was having sex with Lilliana.

The MC quickly rejoins afterwards, so it remains a foursome for the rest of the scene.

Better Girls – Chapter 6

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Chapter Link
Rating: 5

Ai finds Syurina masturbating to the MC’s clothes after he rejected her. Ai wants to help and cheer her up, so she starts seducing and fingering her.

Ai then takes her to Momo and Tohka, asking them to help teach Syurina “The pleasures of being a woman.”

We see it in Ch. 8, but it’s implied after this chapter that they have lesbian group sex in the locker room every day.