There are some things Remus isn't willing to do. (Mild slash suggestions.)
Eat crackers. In the first place, he couldn't afford crackers; second, he couldn't afford to get kicked out of bed. On the other hand, if he had crackers, he would eat them, crumbs or no, and there was no one to kick him out of bed for it anyway.
Pass a full moon. Once, long ago, Sirius had suggested staying in his room, convinced Padfoot would be enough to handle the wolf if it was chained to the bed. Miss Rouault on the third floor saw Sirius bringing up the chains, and what with the banging and rattling and howling that followed that night... His neighbours never looked at him the same way again afterwards.
Clip his toenails. (not after that time he caught Severus using a stray clipping to make a potion of some sort that he refused to identify.)
Allow himself to be undressed. Clean underwear was one thing, but clean underwear that was darned and tatty, grey with age and all but worn through did not look that different from dirty underwear. (also, he worried it might give Severus flashbacks.)
Read the romance novels he sometimes borrowed from the back of Severus's bookshelf. Invariably, someone would look up wistfully at the moon, or the couple would kiss in the moonlight, or something like that, and he would dream about hunting.