From Good Girls Scan BL:

Kouta and Tougo are childhood friends who live in Kansai. Kouta, who loves sweets, made a promise with the successor of a Japanese confectionery shop, Tougo, when they were kids, being that they would get married if the latter could make delicious Kaiten-yaki. After becoming high school students and confirming that neither of their feelings have changed, they became lovers and were lovey dovey every day. Though recently, a popular western confectionery shop has opened nearby, and Tougo's shop is in a big pinch! Furthermore, when Kouta accepts an invitation from the handsome store manager of the western confectionery shop, Satoru, the relationship between the Kouta and Tougo takes a turn for the worst...?!