She didn't know how to comfort people. Despite her telepathy giving her insight into what went through people's minds, Tatsumaki still felt immensely awkward trying to connect with people. She normally kept people away. So why did she feel a pull on her heartstrings right now? Why wasn't she just crossing her arms and walking away like usual?

Probably because she understood loss intimately.

"Who did you lose last fall?"

She'd done the mental math. If Orihime didn't really remember her parents, then someone had been taking care of her in between their deaths and when she moved in to live with her aunt in the past fall.