I'm The Only One You Should Love: My Childhood Friend's Love Is Too Deep

High school student Mugi Hoshimi has a crush on Nagisa Kuon, a childhood friend. However, Mugi has been unable to express her feelings to Nagisa because of her body's sensitivity: she is stimulated by even the slightest touch, and she is afraid that Nagisa will find out and hate her for it... She attempts to evade him, but Nagisa comes on to Mugi with a strong love that won't allow any other man close to her...?!

(Source: MangaPlaza)