Once Isabella goes to the prison to talk to Claudio, she finally tells her brother what Angelo said. At first, Claudio totally agrees with Isabella's decision. He says "thou shalt not do't" (Line 116). It's up for debate on how this line would be performed. I felt the sincerity and that he knows how important Isabella's chastity is to her. He had to know she was working on becoming a nun. This makes me very much Team Claudio. For him to say this first before questioning Isabella's descion, means a lot in my eyes. Once he does question the proposition, it's not like he's mean or harsh to Isabella. He basically says "it wouldn't be too horrible if you slept with Angelo".
If my sibling was in a terrible situation and that was my only option, Angelowould definitely have to be decent looking for me to consider it. I'm sorry, but if I'm saving your unlawful ass the man better be somewhat good looking. I do, however, understand why Isabella chooses not to follow through with the plan. Their time period and today's time period are EXTREMELY different, especially with perceptions of premarital sex. If Isabella chose to sleep with Angelo, her life would be literally over; no nunnery or even respect from anyone. It would even get better after life; hell for eternity!!!
Overall, I understand Isabella, but I would totally save my sibling regardless. It would be different if Claudio had committed a horrible crime. All he did was sleep with a woman he loves and plans on marrying. It's not right that Isabella is being asked to break the very same law to save her brother, but what other choice is there?