So from what I remember the movie was about a man living in the sewers who looked a bit like a deformed rat or beaver and he fell in love with a woman. That’s all I can remember unfortunately.
- Saw it about 15 years ago but it might be older
- It was probably in English
- Saw it on TV
- It was in colour
Ratboy (1986)?
https://www.imdb.com/title/tt0091827/?ref_=fn_al_tt_1
You may be thinking of the “Beauty and the Beast” TV series from the late 80’s
https://www.imdb.com/title/tt0092319/