Will is an agreeable student with a tendency to try to please the people around him; being seen as a people-pleaser because of this. Although, while Ada does this for status and power, Will’s intentions seem more genuine, as he’s extremely loyal to Montresor even when Montresor doesn’t treat him well.
Will doesn’t dislike anyone, and is even respectful towards those on Lenore’s side. When Montresor is around, he’ll do what he’s told, even if that involves taunting or otherwise being rude towards people.
This is shown when Montresor is making fun of Ada and requests Will to join in. Even when Will is laughing alongside Montresor at Ada, though, the only thing he tells Ada to do is “say something nice” about him. This implies that Will is fond of positive attention or praise, hinting towards him being attention-starved.
This could imply a reason as to why Will is so insistent on following Montresor, as well, as he seems particularly attached to him. He acts on Montresor’s words, even when it seems like it’s something that goes against his own morals or makes him uncomfortable.
When without Montresor, Will is a significantly lesser threat, not starting conflict on his own or posing any trouble.