Yamada, a kind-hearted and well endowed high school girl, comes across Takahashi, a high school teacher, who was taking a nap near the forest as he's got a lot on his mind. Lost in their own little world, Yamada helps unravel Takahashi's troubles with her soothing kindness...
Yamada and Teacher is a completed manga by Igarashi Ran (五十嵐藍), first published in 2019. It blends psychological and romance. You can read all 7 available chapters of Yamada and Teacher online for free on MangaPulse; the newest is Chapter 7, added 2020-10-26. The series is finished, so you can read it from start to end in one go.