It's not okay to judge people on size.
Paul is friends with Erica who is thin but feels insecure about how she looks.
Paul wants to boost Erica's self-esteem.
Paul tells Erica that she is a great person and a great friend who many people love.
Paul tells Erica that she looks great and that compared to their larger friend Hannah she is much more attractive and seems healtheir.
Erica feels better about herself and appreciates Paul's kindness.
Erica is angry that Paul would insult Hannah like that and tells Hannah about what Paul said.