Sweet Sugar Sweet

Rio, a confectionery student, is captivated by a cool and kind guy he often sees on the train. One day, when he struggles to board due to the overcrowded car, the man steps in to help him and introduces himself as Hasumi, a police officer. Since that moment, Rio has found himself lost in dirty fantasies about Hasumi every night. As he continues to see him each morning on the crowded train, his heart races with growing affection...

(Source: Frontier Works, translated)

Note: The chapter count includes an extra.