Its not like she can hide it from him, its him never cared about romance. He never was able properly develop in that aspect after incident in a flashback. Emotional traumas more often than not prevent people growing after experiencing them, forcing them to be stuck in the past.He says "its obvious, watching you" which is true, but it reminds me that shes still somehow a master at hiding this side of her from tomo(i think the only time her disguise slipped for a brief moment was when she was sick). I get she doesnt want him to see that side of her for fear of rejection or whatever but you really gotta admire the tenacity in not showing any lovey dovey feelings to the man you love. Kind of infuriating, but whatever you have to do to keep the seies going ig.
Thanks for the chapter
We can even draw a parallel in there, he would never outgrow her while still brooding over it. Hence they heights starts to change when kohai introduced in the story.