Binbougami ga!

Synopsis

Figuring she needs a boyfriend, Ichiko takes an interest in her sleepy classmate, Keita Tsuwabuki. Upon finding and returning his ID card, Ichiko is invited by Keita to have dinner with his siblings, who are quite poor as their parents had left them. Keita soon takes a strong dislike to Ichiko when she rejects his ideal that being together is more important than money. The next day, Ichiko tries to make up with Keita's brother Ryūta by buying him a super rare trading card. However, he ends up dropping the card down a sewer and gets trapped in there whilst attempting to retrieve it just as a typhoon starts to settle in. As Ichiko is told by Keita how he doesn't want to be in anyone's debt, Momiji makes her aware of the danger Ryūta is in, prompting her to go and save him. As Ryūta gets swept into the river, Ichiko dives in after him, using a device given to her by Momiji to use her fortune to rescue him. Afterwards, Keita and Ryūta give their thanks to Ichiko, who feels a warmth in her heart.

(Source: Wikipedia)