Go-toubun no Hanayome S2 - Episode 11 - Yotsuba Feels the Flames

Yotsuba noticed her sisters had designs on spending time with Fuutarou and felt their competitive spirits.

Yotsuba worried that Itsuki might be buying underwear for the school trip to Kyoto because she fell behind her sisters in the bust size department. On the train trip to Kyoto, the other sisters again left Yotsuba out of their fiery competition for Fuutarou's time, with Nino declaring their card game to be the decider. Unfortunately for those other girls, Yotsuba won the game and told them what to do so Miku could spend lunch with Fuutarou.

Disaster struck Miku's plans when Fuutarou overheard Yotsuba arguing with her sisters and he heard that Miku planned to confess her feelings to him. I think he knows how she feels already... But anyway, Miku felt embarrassed and shy, so she holed up in her hotel room with Nino taking care of her and supporting her emotionally in her own way. Both girls won't give up on Fuutarou, however the big revelation of the episode was that Yotsuba learned the little girl Fuutarou met as a boy in Kyoto was his first love and that she was that Nakano sister! Yotsuba slotted into first place in the Fuutarou sweepstakes without even trying.