Chiaki is a lot of things. He knows how to be a lot of things. He’s a complex character, and it takes a while to unpack all the aspects of his personality. At the office, he’s a suave gentleman with a sweet face and a kind smile. An excellent worker, everyone expects great things from him. However, catch him at the wrong moment and you might find him being cold or cruel or manipulative.
And manipulative he is. There’s no denying it. He uses people, and he sees the MC as an vurnerable target. Somewhere the MC knows this too, and she tries her best to be on her guard around him. I think that’s why he teases her and tests her so much. In a way, he’s both warning her to be careful and throwing her off guard so he can take advantage.
kind of big spoilers under the cut