Any romance anime’s that are still quite “modest” In the beginning but get more adult rated in the end/last ep?

I REALLY love romance anime’s and really don’t enjoy the anime’s that are super ecchi just over the top with fan service. But I’m dying with the slow burn anime’s and need SOME type of action.

To be clear, I just want anime’s that have the main character and love interest kinda lean into their desires just a little, it doesn’t have to be all the way… also preferably not super quickly too… I want some build up.

Any help would be appreciated!!