Lucas Nelson is an original Loud House character created by TrevorPhillips for his show The Adventures of Lynn Loud. In that show, he serves as the boyfriend to the titular main character of the show, Lynn Loud and Lucas is often seen hanging out with Lynn or occasionally as a background character. Lucas is a 13-year old boy who is taller than Lynn (he is around Luan's height), has white skin, has blonde hair, and he often wears a grey shirt with a black jacket. He is very kind and sweet to everyone around him, with the exception of Tyler White, who often tries to steal Lynn from him. He lives with his mother since his father divorced from him and he moved away to New York City. Lucas Nelson has one older brother, Jake Nelson, who is 16 years old.
Lucas Nelson also appears in another spin-off, The Lincoln Show by Nat Garcia, who is potrayed as a 38-year old and is an ax-crazy psychopath, under Trevor's approval. Despite his approval, however, he does not consider this canon to his show.