The current exchange between Max and Ash resulted from that type of situation where they got lost in the heat of the moment and dropped their inhibitions.
It happened once, which left them both feeling like they did not know how to handle it, but they allowed it to happen again and again until it started to feel more natural.
Ash never planned to start a relationship and to get too emotionally involved, but such moments did feel quite pleasant despite previously being so against such a thing happening and rejecting the idea so much.
It was natural for her to feel stressed out and have other emotions boiling up after being so busy and pushing herself daily without having anyone else to rely on.
Not many could shoulder everything alone, and many needed to unload onto others; otherwise, they would soon reach a point where they would struggle to cope, and they would become mentally or physically overwhelmed.