I think that Yeojae's character has a lot of depth and I think the author did good in pacing out the story to reveal more of his character traits. We know why he acts the way he acts, he's always wanted to appear normal to Seoyun his whole life. Examples: He dated girls without any emotional connection, he made efforts to smile more, he controlled his violent urges. That's why he froze when Seoyun made those comments when reading the scrapbook, he needed to be seen as normal because he thinks that's what Seoyun wants. Yeojae had already planned out what his life with Seoyun was gonna be like and couldn't fathom that he could even pursue him in a romantic sense since his logic was based on the fact that dating was only for reproducing (hence his image of the future for Seoyun was him having a kid). And now that I think about it, even the homophobic remarks he made were probably not based on his own opinion but rather what society would deem 'normal'. I wanna see the further developments of his character and if his way of thinking changes.
He decided to walk instead of taking the car