Is it suicide for onion to kill giant Yum and then die?

Onion used to be friends with Youm, but Youm didn't accept the fact that he became the king of sin capital, and the sin fire of sin capital came from the abyss. In order to prevent himself from being eroded by the abyss in the future, because no one can stop the giant's physique, Youm revealed his weakness-the only weapon that can knock down the giant: the storm controller, two, one stays in the sin capital, and the other entrusts his close friend Onion, hoping that Onion can stop him from losing his mind. The undead will get rid of the shackles and rest in peace after they get what they want. As a fairy, the only thing onion cares about is the agreement with Youm. After the protagonist helped Onion kill Yum, Onion committed suicide with a storm controller covered with his friend's blood, got rid of the curse and bondage, and slept beside his friend.