Noah's lack of self-control was one reason why Diego did this, the other because both of them wanted something from it and Diego was willing to risk his safety with Noah to get what he wanted. If anything, this was a good learning experience so Noah could control himself better in other situations than this.

Seeing Noah with his tie between his teeth made Diego breathe a bit more heavily. That changed when Noah pushed the air out of him and he gasped and groaned, trying to get his breath back while taking in the pain from the weight of the demigod on him. He looked up at him and bit his lip to keep any sound from coming out. Noah needed to force things out of him, after all and Diego was going to encourage him to do so.