I just watched episode 14, of season 4, of Haikyu on VRV / Crunchyroll. I was already a big fan of Tanaka’s older sister, Saeko, but I’m an even bigger fan now.
Saeko is her own person, she lives life to the fullest, and she has such an energetic sense of being that she positively influences those around her. Plus she is confident, loves to laugh, and have fun. Saeko supports her brother and his teammates, even driving them to practices, and cheering them on during their games. She plays the Taiko drum, and she and her friends showed up just in time to support the Karasuno volleyball team during Nationals. They played a large part in easing the pressure the team felt on the court. It’s understandable why Nishinoya and Hinata reacted the way they did.