Muchi Nochi Tsugai

When Satsuki, an omega, hears about the concept of fated mates, he says that if he could meet that person, he would meet them. On his train ride home one day, he suddenly smells something sweet and wonders if it's the pheromones of his fated mate. Sadly, he doesn't find that person in the crowd, but little does he know that Asahi, an alpha, is there and smells the same sweet scent. (I found the synopsis on MU and completely rewrote it, since it wasn't written well on there.)