person who is satisfied with their real (offline) life; normie
fullness; completeness; perfection; substantiality
彼女はリア充っぽいね。
She seems like someone with a full life.
リア充の投稿を見ると羨ましい。
I'm jealous when I see fulfilling posts.
いつかリア充になりたいな。
Someday I want to have a full life.