Rei is surprisingly tolerant of Shougo's childish and eccentric personality, likely because he has a considerable measure of control over him. He can easily convince Shougo to do various tasks for him and distract him very easily, which is something that no Sena family member has accomplished. Based on the 11th and final episode of the anime, the last minute of the episode suggests that Shougo kisses Rei during their ride in the Ferris wheel in the amusement park that Izumi and Ryouma visited for a date. Shougo says he wished to visit the amusement park because he also wanted to go with Rei there. He is then seen moving across the seat towards Rei, but a light is promptly flashed off the glass just as he reaches him. The anime ends there, leaving alot of suspense about the possibility of their relationship being anything but professional (in the least for those who haven't read the manga or light novel).
He likes dick