Mustard/Relationships

Muscular
Mustard and Muscular seem to get along well enough despite their opposing views on strategic planning, Mustard believing that it's best to wait for the right time, and Muscular believing that it's best to just attack now and worry about the details later.

Himiko Toga
Mustard considers Himiko to be impractical, as he criticized her for caring more about whether or not her support gear was cute than for the equipment's functionality.

Tetsutetsu Tetsutetsu
Mustard and Tetsutetsu ultimately hate each other. Tetsutetsu holds a grudge against Mustard for using his Knockout Gas to hurt his classmates and for the League of Villains invasion ruining the Quirk Training Camp. He is initially surprised that the gas villain was roughly his own age.

Mustard on the other hand can't stand that someone so loud and straightforward with such a basic fighting style is praised simply because of his school's reputation.

Itsuka Kendo
Mustard considers Itsuka and her Quirk to be exactly the kind of person and power he hates, simple and straightforward. He initially thinks of her as just another unremarkable who's praised because of where she goes to school. He was surprised when he saw the power she could achieve with her enlarged hands.