One more slice of ReiKoga angst for the road because I've fallen and can't get up.
Naturally, Rei's health fails first. Unfortunately early too, around his late 60's. Koga steps up immediately to provide care. He makes a dedicated nurse with questionable bedside manner, but Rei expects nothing else. Sometimes he acts difficult and whiny because he can't stand seeing Koga depressed. Rei would rather piss him off just to make the sadness stop for a bit, intentionally flare up the wolf's wild side so he can leech off his potent life.
Even after decades together Koga still has hero worship for Rei. The whole point of UNDEAD was kicking death's ass and choosing to come back to life. He's sure Rei is gonna get better, because Rei Sakuma can do anything.
He doesn't. Rei dies unfortunately young, and leaves Koga feeling lost. Koga doesn't know what to do with himself without the guy he followed like a disciple. He sinks into a lonely depression others can ease but no living person can heal. Whenever he's alone he berates himself for every time he pushed Rei's affections away out of pride, or impatience, or just general grouchiness. He would give anything for one more smothering hug from that touchy feely vampire bastard.
Eventually, he does start to heal. Koga is the type of spouse to visit Rei's grave often. He spends a lot of time there talking to the headstone, nagging at it, and reminiscing too.
Koga develops a reputation in the local neighborhood as the weird old guy who barks at dead people. But he's not like the other visitors to the graveyard. He never brings flowers to the grave. Instead, the weird old dog guy leaves guitar picks, or old leather gloves, or scribbled lyrics in need of approval he only wants from one person. That makes people curious about him.
Years later, Koga's health is failing too. He totters out to Rei's gravestone with rickety joints, poor posture, and grumbling under his breath. He's brought something special today. That first black and gold guitar he and Rei shared, still meticulously maintained as Koga's prized possession.
He wants to play music with his idol one more time, though the arthritis in his fingers makes even his favorite past time difficult now. After a few melancholy acoustic songs, someone interrupts him.
"Hey, mister?" It's a teenager. Looks like a rowdy type of kid with a moody crease in his brow, "Is this you?"
The teenager shows Koga an ancient video of an UNDEAD live. All four of them, youthful and full of vigor. A time capsule of some of his most precious memories. Koga blinks away his tears before they can show, "... Yeah. That's me."
"Yes! I knew it! You really were a rockstar! My brother owes me $20, he was sure you were just some weird old kinkster!"
"... Heh. Nah, you're right. I've been makin music for a long time."
"That's awesome! I wanna form a band just like yours someday, but my parents think it's a waste of time. I doubt I'll ever get to be as cool as you."
Koga looks down at the beloved guitar he can't even play without pain anymore. It deserves to be played. He would rather somebody play it then let it gather dust. He holds it out to the kid, "Here."
Koga's grip tightens around the neck. He snarls, "On one condition. You work your ass off. You gotta practice every day, no matter how hard it is, no matter who tries to tell you it's not worth it. You gotta keep playing, cause as long as you love doin it, it'll be worth doin. Got it?"
"... Yeah. I'll take good care of it, and work real hard. Promise, mister."
Koga lets go, "You better, or the spirits of the UNDEAD will come back to haunt that guitar." He rolls an ache from his neck and tosses a wave over his shoulder as he turns to leave, "See ya."
It's a sudden departure, but Koga really doesn't want some brat to see him cry.
He's pretty sure he can feel a vampire bastard smiling at him, though. Just a hunch.