Gilgamesh, whose True Name is not concealed by a class designation, is unable to exist on the Near Side of the Moon Cell due to his strength, so he is only able to exist within the Far Side. He simply passes away the time sleeping due to nothing being able to exist there, but his physical body awakens with BB 's restructuring of the Far Side.
He is offended when people think his height is more normal than expected. He believes that there is no excessive flesh and weight, ever since he was born. His response to his three sizes, he claims to possess a golden body; befitting the golden king. It is far too beautiful for others to see, but if you desire him to cast off, bring forth a command seal. He likes wearing golden color underwear. Gilgamesh's personality is heavily influenced by the era into which he is summoned.
He has taken a liking to the virtual world of , so his personality is more stable and closer to how it was during life. PH, and decides to simply do as he pleases. This later changes when he personally declared that the fight against BB has also become his battle. Gilgamesh likes to tease his Master, and he even goes as far to ask the female version "Who is the man you want to be held by? He believes that there can be nothing else between a man and a woman. He restricts it to the Student Council members, but he will be annoyed if he is chosen instead.
He takes it as a given that he is already the obvious choice, so it is useless in staving off boredom. He says it was unavoidable due to being exposed to his aura at such proximity and forgives her, but also completely rejects her, mentioning that she is four thousand years too early for him.
He prefers "a noble maiden", "a virgin", and "a flower that blooms in the plain" was his type during his childhood. He believes that he has no weakness and has no faults.
