Not being able to turn down a kiss after receiving oral sex.
Shit man, she gave me head but I forgot about Oral Obligation.
The thing on every man's mind after receiving head is oral obligation.
My boyfriend is so weird about Oral Obligation, now I make out with him for 20 minutes after Oral on purpose!
Someone who must to their job, for example: doctors are obliged by law to keep patients alive while there is a chance of recovery
Assasin/killer: So I said to the Baker, your not dead, you're a faker. But If that's your wish I'll oblige.
to make someone do something as in forcing him/her
The emperor obliged his commander in chief to kill an innocent child.