From DMP:

"The person I love is you, Haru!"
Haru is shocked by the sudden confession from his best friend Kazushi and the passionate kiss that follows! However, he can't bring himself to see the perfect and widely admired Kazushi as anything more than a friend. Determined to win Haru's admiration and love, Kazushi steals a kiss every chance he can get. How long can Haru ward off his increasingly strong and bold advances?

Higurashi Yuuto gets picked up on the street but it turns out that the good-looking man is Oohataya Masakazu, a schoolmate from his junior school and a shinto priest at the Azuma Shrine. How is Yuuto going to react since he's Masakazu's first and second love?

The side story involves Yuuto's superior, Uekusa, and Yokoi, Uekusa's former subordinate.