I may be combining two stories but the mc girl was feeding cats or something and said I like you to a guy that always has a really scary look on his face and not the person she meant to say it to.
but he turns out to be really nice. It took her some time to realize that but since she confessed they started dating. He later finds out she meant to confess to someone else and the relationship ended. But I think it worked out in the end

If you know this story or something similar tbh please let me know~

Wrong Confession