I'm looking for romance manga that feature feature characters in at least their 20s or 30s. Novel recommendations I could appreciate as well. Thank you.
In my opinion, Baby, Kokoro no Mama ni! is an absolute hidden gem. Don't let the odd cover dissuade you because I consider this to be one of my absolute favorites. It's funny, cozy, and sweet. The only problem with it is the author is on hiatus because she decided to start a family herself. Give it a read.