It might just be them changing but when Chloe talks about Theo her eyes have a slight pink to them (Especially on this page: https://www.mangago.me/read-manga/my_three_tyrant_brothers/uu/to_chapter-24/pg-12/). The way I see it, I think it could be the beginning of love. Like right now it's probably a childlike love, or one found when having someone who went through and is currently going though thing similar to you. I feel like it will grow over time
It might just be them changing but when Chloe talks about Theo her eyes have a slight pink to them (Especially on this page: https://www.mangago.me/read-manga/my_three_tyrant_brothers/uu/to_chapter-24/pg-12/).
The way I see it, I think it could be the beginning of love. Like right now it's probably a childlike love, or one found when having someone who went through and is currently going though thing similar to you. I feel like it will grow over time