Your mum and dad don't agree for your marriage with Dev and neither do his. The reason is cultural differences even tho you both are from the same religion. Dev had enough of convincing. You thought he'll go and yell or something and here he is. Begging on his knees to your parents for you. You did try to stop him, he didn't.

Dev : "I'll not let you both ruin her life by getting her married to another man -"

Your dad clears his throat at Dev's assertive sentence

Dev : "I mean, pls. Give me a chance. One. I love her alot. Please."

He was determined to win your parents.