InCha na Ore ga Madougu o Tsukatte Share House de Harem o Tsukutte Mita. – Chapter 13

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Rating: 4

While the MC is having sex with Shieri, Rin and Ann briefly join in by groping Shieri.

While they’re sucking on her breasts, 1 of them mentions how they did this all the time in the past, implying they’ve had lesbian threesomes before.

Eventually Rin and Ann stop to just have lesbian sex with each other in the background.

So I’m gonna tag this as Male Involved, but the MC doesn’t do anything with Rin and Ann after they leave to have lesbian sex.

The Caretaker of Tenants from Another World – Chapter 67

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Rating: 4

The MC tells Elaine where the bathroom is so she can take a bath, but he soon finds out that Ange was in there as well. He goes to check on her, but when he knocks on the door, nobody answers.

Later, Ange and Elaine appear at the dinner table, with Elaine blushing and Ange smiling, the MC knows that something happened between them.

After that, they keep disappearing throughout the night, implying they keep going off to have lesbian sex with each other, but it’s not shown.

Cheating tag is here because this is the only time Ange has sex with someone without the MC’s consent after they started dating. He even makes a joke about it next chapter, but he’s fine with them having sex with each other.