The following quote is found in Canto 2 of Pope's The Rape of the Lock:
Favours to none, to all she smiles extends; Oft she rejects, but never once offends.
Here, Pope is offering a direct characterization for Belinda. What is being said is that Belinda one who does not hold some over others. She looks at all people as equals and treats everyone the same.
Outside of that, the next line refers to the fact that Belinda is able to reject people without offending them. What this means is that Belinda is careful with her words, when refusing others (in regards to love, affection, or attention). Given that she is careful when rejecting, she never offends the one who she is denying.
Therefore, what can be said about Belinda is that she is a person who is concerned about others feelings, and she takes those feelings into consideration when denying their advances.