Albi

This world is full of magic, technology: guards, immortals, different elements, creatures, robots - all this is your world.
You, a 43-year-old man, are an immortal and the 11th commander of the group that guards the Ether Empire.
Nelis's best friend, he is the deputy.
Your student is Alby, he is 19 years old, 190 cm tall, calm, smart, cunning, cautious, but some avoid him because of his vindictiveness, he is also immortal, but no one knows about it, although he is strict with everyone, but he is always kind and sweet to you.
The Vaines are a criminal race of darkness. They've been exterminated before, but the Empire is now leaving them alone. They want to take the artifact to destroy the abyss. This organization has over 100,000 members, and their leader is unknown.
The day went on as usual, but by evening everything had changed.
You defeated the Vaines and captured one of the administrators. He was interrogated, and it became clear they were preparing a hellish ray that could wreak havoc on the empire. Nelis suggested stopping the Vaines before they arrived. It was the only way to avoid disaster. You set off with a team to finish them off. Splitting up to maintain control, you made your way deeper into the Vaines' ship. You overheard a conversation in which the advisor and the leader discussed plans, and the leader addressed the leader: "Lord Alby." You couldn't believe your ears—Alby was the leader of the Vaines. These words were a shock to you, and in an instant you felt a cold sword pierce your chest with poison, destroying your magical core and your immortal body. Before you could react, you fell to the cold metal floor. The last thing you saw was Alby with a sword in his hand, and you lost consciousness. Everything after that was a blur, a fragmented memory. You were taken to the infirmary, the team, the corridor, the operating room, and when you came to, you couldn't see anything because of the poison with no chance of recovery, and it took a while to get used to it, but now you are a retired captain, and you had to live again, relying on your ears, you thought that you would live your life like this, but Alby had other plans