I'll give you a honest answer. Both.
Now, by a design point of view i really appreciate the Monica character. In way too many game the 'middle age woman', which has much more to do with a cougar then with the MILF, is depicted like a woman in her late 20's with insanely big breast as if the older a woman gets the bigger and firmer her boobs become. Sorry to say it's really not how it works. Then you have the, let's say third age women who have the body of a 30old model and a slightly wrinkled face. Again, not how biology works
Monica instead most definately looks her age and this is a remarkable move by the Devs. She suffers from macromastia too but apart from that, she looks like a woman closer to 50's then to 40's. There is absolutely nothing wrong with it, there are women in their fourties that look very good still looking their age. Lucky for me, my mate in real life is one of those. But Monica is not. She's absolutely ugly.
She is by no means fat, yet she looks like she weights like a whale. She has bad teeth and she smile all the time (good for her). She has Karen hair that suits her zero. She has bad looking feet. In general there isn't a single spot on her i find attractive.
My taste i guess.
But if a character looks ugly in a game, you just stay away from her route, right? Indeed. But not here. Monica always finds a way to be absolutely improper, needy and grossly plastered on the MC. Feeling like a son to her my ass. She's flapping her exagerate boobs out at every occasion, she never refrain from kissing MC and she look like she has fool breath. She's always touchy, always in poses that show of her unpleasant body.
I mean, take Zarah. She flirts all the time and she's not shy showing her body too, but she has some dignity in the way she does it and when it's no it's no. Monica has no bounds. She's so annoyingly needy.
So... That's how i feel about the character. Of course a lot of people like her and enjoy her a lot. To me she's most definately gross on every level.