Hi there! Sorry about the delayed reply. I've been really busy juggling work, a new Soulsoft EA VN and also collabing on a game for YaoiJam 2018.
There is definitely a way for Sato to like you. But first you must avoid all the other guys throwing their advances at you and ending up on their routes...like Marlain, That's the main thing. Then, after Jaja discovers Sato has feelings for you too...you must pick to meet with Jaja NOT Sato. Sato will be so impressed that you put his brother first (like he would) that he decides to give you a chance. Goodluck!