THOMAS:
SpongeBob. He has a slight obsession of color yellow and sponges.
NEWT:
Phineas and Ferb. Because these two characters are really intelligent.
MINHO:
Mickey Mouse. Because Minho's name starts with a letter 'M', his favourite character's name also starts with a letter 'M'. That's the rule.
GALLY:
Barbie. He's always saying that you look a lot like Barbie. And...that feels great.