Dongsaeng is a Korean word describing a family or friendship relationship. It is used to refer to one's younger sibling or a close friend that is younger than oneself.
"I promised my dongsaeng I'll treat her for dinner if she did well on her test."
(Although the above statement is a command, 'dongsaeng' acts as a form of endearment like 'little brother' or 'little sister'. In other words: "Lil' bro, how about a cup of coffee for your big bro?")
Donglirious is a state a person has fallen into when they have had either to much or have had access to zero dong at all, resulting in the subject becoming delirious.
Man oh man, did you hear about Alicia? I guess Barry was dishing her the dong all weekend long, and as a result she became Donglirious and had to miss work. Of all the things you can miss work for in today’s age, she’s missing it due to a serious intake of the old third leg. Sad and yet beautiful at the same time.