Mallory is one of Beverly Beverly High's most beloved students. She is nice to everyone she knows, including Spencer Wright, even when he is considered responsible for spooking her into leaving Beverly Heights. People become dismayed if they do so much as see her frown, because she is so well-known among her community for being a kind person.
Mallory is considered to be a very pretty and popular girl by everyone at Beverly Heights. Her attractiveness is only enhanced by her stellar reputation and gentle, friendly demeanor. She is very close to being The Most Perfect Girl in The Whole Wide World.
In fact, she's so appealing that Spencer is harboring a fairly obvious crush on her. Naturally, Billy Joe Cobra tends to make Spencer look bad in front of her while he's trying to ask her out, so the two never really get anywhere.
She is somewhat passive in her kindness at times. She doesn't stand up for Spencer whenever Principal Ponzi or Lolo Calorie decide to be unfair to him, and laughed a little when she overheard gossip about Spencer. In addition, when Lolo spread lies about Spencer in Reality Showdown, she chose to believe the conniving Lolo rather than trust Spencer. (She soon learned her lesson when she found that Lolo ignores her messages because she "doesn't want to hear about her problems".) She also shows no concern for her fellow students when they're forced to spend school hours in a tiny trailer.
Still, she does stand up for Spencer when Kleet is being an outright bully to Spencer, and she seems to have a good opinion of him, despite what happens when he tries to ask her out. It can be assumed that Mallory is still a teenage girl, even if she is really nice.