Frank seemed to have quite forgotten that such a person as Roll Ditson existed.
Ditson was an outcast.

The fellow with whom he had roomed had left him shortly after his treachery was made public, and he was forced to room alone, as he could get no one to come in with him.
Roll did not mind this so much, however.

He pretended that he was far more exclusive than the average freshman, and he tried to imitate the ways of the juniors and seniors, some of whom had swell apartments.
Ditson's parents were wealthy, and they furnished him with plenty of loose change, so that he could cut quite a dash.

He had fancied that his money would buy plenty of friends for him.

At first, before his real character was known, he had picked up quite a following, but he posed as a superior, which made him disliked by the very ones who helped him spend his money.
He had hoped to be a leader at Yale, but, to his dismay, he found that he did not cut much of a figure after all, and Frank Merriwell, a fellow who never drank or smoked, was far more popular.