Mick Swagger is a recurring character in The Loud House. He is a famous singer, and the leader of a rock band (whose name is still unknown). He has had his rock career for over 40 years. Luna is a big fan of him, and sees him as her hero.
Mick is first mentioned in "Making the Case" by Luna, where she was imitating Mick's rock pose, ripping her pants in the process.
He makes a brief cameo in "Sleuth or Consequences", being pursued by Luna to obtain a lock of his hair during a concert. This was his first physical appearance on the show. He later appears in "Butterfly Effect", in which he asks Luna to join him on his tour after a song she records about her family's misfortunes becomes a big hit on the Internet. However, this is revealed to have only happened in a worst-case scenario that Lincoln had imagined as a result of him not telling Lisa that he wrecked her chemicals.
Years before the beginning of the main series, Mick gave a concert when Luna was in the 7th grade. She assisted to the concert, which the first one she'd ever been to, and witnessed Mick on stage singing, as if calling out to her. She took the stage with him, and suddenly found that the world of rock was where she was meant to be. Since then, she has seen Mick as a hero in her eyes for giving her the inspiration to rock on.