Did this to the wife the other night. Not sure she loves it, but she's into it when I request.
I realized about half way through sex that she was still wearing her glasses. She on on her back on the couch, ass on the edge, me on my knees on the floor fucking her.
So when I was close, I told her I wanted to cum on her face and glasses. Stood up, leaned in, and unloaded.
The funny part was she said "Wow that was hot." And I thought "Cool, she's really into it." Then she said "... like it's always pretty warm, but your cum actually seemed really hot this time."