Because sometimes letting her walls down and physical closeness is all she needs.
After a busy day full of adult responsibilities, they meet and crash on his couch, relaxed, tired from the day, content to just spend some time together and finally sit down, talking a bit, sharing a warm drink. A relaxed escape they sometimes share, unknown to the rest of the world.
They are sitting close, his arm around her, her head resting on his shoulder, both with legs stretched, barefooted. He is fully dressed; she is topless, a blanket covering her lower body. His hand occasionally caresses her breasts, teases her nipples, how and when he desires... it's not a sexual advance, it's their way when occasionally together, it meets their mutual needs.
They enjoy the closeness, feeling no pressure or expectations, both just being... there, safe, in the moment, nothing of the outside world or daily life interrupting.
They watch a show, talk about everything and nothing, their hands caressing each other unhurriedly, just for the pleasure of touching and being touched. Enjoying each other's presence.
He gets up to refill his drink and to warm up her now cold tea, half an erection in his pants. She is slightly aroused too, nipples hard. He could have asked her to go, but this is his place, and he likes caring for her, as she does for him. It's in their nature, who they are. They've agreed to be their honest self with each other, in person or remotely. No walls, no games, no BS.
He comes back to the couch, places the refreshed drinks nearby and, thinking she is too dressed for comfort, removes her skirt (Mmmm no panties... his preference). She smiles.
Moving her so she is laying down, he replaces the blanket on her, lifts her bare shoulders, and sits with her head on his laps. They watch the end of the show, his hand exploring her body a little more, her teasingly caressing him. The show ends and he raises her up beside him for a kiss, gentle at first then becoming an explorative question. He is unsure what he wants.