I am looking for a story about two friends. Uke - short, blond, cheerful and Seme - tall, dark-haired and quiet. He had been friends since childhood and always holding hands. After some time, uke says "enough" but he can not get used to being alone. I do not remember it was a one-shot or the whole story. Please help.

Hello my friend!
I'm sure you are talking about Kimi to Iru Asu chapter 5.