TutoringNTR!? Having sex with the neighbor's total affirmation sister…! ASMR

The male protagonist is troubled by the inability to have comfortable sex with his girlfriend.
The person he turns to for help is the gentle older sister living next door, named "Maina".

One day, our troubled protagonist accidentally wandered into the neighbor's room, overwhelmed by his worries.
With the caring support of a gentle older sister figure, he opened up about his troubles
—specifically, the difficulty he was having sex with his girlfriend.
Little did he expect that the kind older sister would take it upon herself to provide him with coaching on improving his Ｈ skills!