I’d probably argue games that ‘can’ do this well is JRPGs because they tend to be a slow burn and have a lot of small side conversations that are not directly plot related, which allows the characters and relationships to get fleshed out.

The ones that immediately come to mind are FF 8/9/10 but I’m certain there are others.

In games where the romance is like a mechanic and not a part of the story? Hmm that’s a tougher question because I think mechanics/gameification tend to ruin the human part of relationship building.