Deadass

The most sacred of promises. Deadass is ONLY used when you're completely and entirely honest about something. To lie when using Deadass would be like breaking a pinky promise, which would be the lowest thing you could do. You can either say Deadass, or say no and explain how you feel about something. You can lie, sure, but when Deadass is used, you have to be completely and entirely honest regardless of how embarrassing it is.

"Yo do you want to go to that party?"
"Yeah."
"Deadass?"
"....no. I don't really want to."