I'm Here, Beside You manga volume 1 features story and art by TEA natsuno.

Ibuki Doi has never forgotten his first love from high school—Mikami Baba, the kind, handsome, and totally straight student council president. Though he was too shy to approach Mikami back then, Ibuki always held his idol near and dear to his heart, wishing him nothing but the best! However, when he learns Mikami is soon to be married to a man, he just can't help it—he's absolutely devastated. He drinks himself into a stupor to drown his sorrow but is surprised to wake up and find…he's back in high school?! Could this be Ibuki's second chance to make things go his way?