Kaa-chan — No Tomodachi Ni Shikotteru Tokoro Mira...

The protagonist is caught in an intimate moment. The "friend" often enters the room under the guise of looking for the mother or bringing a snack.

It scratches a very specific itch. If you enjoy stories where the power dynamic is flipped by an older, experienced woman taking the lead, this is top-tier content. It avoids the pitfalls of overly complex plots and focuses purely on the chemistry between the leads. Kaa-chan no Tomodachi ni Shikotteru Tokoro Mira...