Koi no Cupid no Onee-san VS Shoujiki Sugite Furare Makutetta Koukousei

High school boy Ryoki Toraga is too honest and straight-laced to attract a girlfriend, until he was visited by a cute savior from heaven! But who is she? Elle is an angel who is awkward in love and in her work, as she keeps getting flustered by Ryoki's straight-forwardness! With the help of the other girls around them, their search for "The One" is off to a wild start! (Source: Pixiv Comic, translated)

This is a romantic comedy RTA manga in which the protagonist reads the signs and makes a preemptive move to make a girl with a problem happy in every parallel world.