"HAPPY NOW, ARIEL?" refers to the twin sister (Ariel) of the creator of Gravity Falls, Alex Hirsch. In a few interviews, Alex mentioned Ariel was a huge fan of Lance Bass when they were younger. When Alex had an episode featuring a boy band, he figured he might be able to get Lance to voice a character, which he did. He invited his sister down while they were recording to meet him, fulfilling one of Ariel’s childhood dreams.