So What If I Became Rei Furuya's Archrival?

Tsukimi Hiruma has a lifelong nemesis.

During his miserable childhood, a beautiful, kindhearted doctor gave him salvation, and he regarded her as his first love. The second time he went to the clinic, full of joy, Tsukimi Hiruma locked eyes with the scheming girl beside the pretty doctor, who had deliberately hurt herself just to see her.

Tsukimi Hiruma: I recognize those eyes. Enemy confirmed.

Later, the doctor moved away with her whole family. For various reasons, Tsukimi Hiruma left the place that had once brought him joy and fell into the abyss.

Tsukimi Hiruma has a lifelong nemesis.

During his miserable adolescence, an upright, kindhearted, tall man gave him salvation, and he regarded him as his teacher. The second time he stepped into his teacher's room, full of admiration, he locked eyes with the gaze in a photo on his teacher's desk. The photo was supposedly of the teacher's rebellious son, who had a poor relationship with him, though the teacher clearly loved him dearly.

Tsukimi Hiruma: I recognize those eyes. This enemy is an upgraded version.

Later, his teacher was promoted and moved away, while Tsukimi Hiruma was taken in by his cousin and moved to a distant land.

Tsukimi Hiruma has a lifelong nemesis.

During his miserable (actually, not really) youth, a shady organization gave him a place to stay, and he regarded it as... well, the target he would devote everything to destroying. The second time he stepped into the room to greet a new member, full of loathing, he once again locked eyes with the new recruit, who was grinning with unusual wickedness.

Tsukimi Hiruma: I recognize those eyes. This enemy is an even more upgraded version, and he's going to steal my achievements.

Later, the two of them couldn't stand each other and devoted themselves to outworking their colleagues, whether red, black, or gray.

(The red, black, and gray factions, forced to join the rat race: ...)

Tsukimi Hiruma has a lifelong nemesis.

As for his... never mind, that's not important. In short, when that satellite came crashing down on Japan, he once again locked eyes with the infuriating person at his side, the one he had to protect for his teacher's sake.

Tsukimi Hiruma: I recognize those eyes. This enemy is an even, even more upgraded version, and he's going to steal my spotlight.

Later, he glowered and took out his anger on the illegally entering FBI first, even stealing their line: FBI, get out of my Japan!

(The FBI: ...)

Tsukimi Hiruma has a lifelong nemesis.

He's too tired to speak. He once again locked eyes with the purple-gray gaze of the lifelong nemesis pretending to be sweet and obedient beside his bed.

Tsukimi Hiruma: I recognize those eyes. This is the enemy who's stolen absolutely everything from him, an even, even, even more upgraded version... his lover.

Later, he made the other man sleep in the guest room that night and felt refreshed, though he was retaliated against afterward.

That counts as a victory, right? After all, the other man practically does whatever he says, except at certain times.

So, my lifelong nemesis, I look forward to spending the rest of my life with you.

Notes:

1. The pairing is as described. The male lead is a certain dark-skinned Public Security officer. The protagonist is absolutely oblivious when it comes to romance, can't take a hint, and is socially anxious, but has a poker face (you know the type).

2. Since the two first bonded through fighting, and spend most of the story disliking each other (especially one certain romance novice), Toru will have to work hard to win his love back (smiling JPG).

3. Toru is reborn and gets himself out of his own death flag. Don't expect someone who only watched a few episodes of Detective Conan in elementary school to save anyone (once again, referring especially to a certain person).

4. In this story, Rei Furuya's father is Furuya Masaaki, and his mother died in childbirth. The characters will reflect some of the author's own interpretations, so please forgive any out-of-character moments. I'm a novice writer, so please point out any mistakes. If I see your comment and think it makes sense, I'll make changes!

5. There will be a little crossover with Katekyo Hitman Reborn, but it's only part of the protagonist's background and won't feature much.

6. There will be a System, but it won't have much presence. In the early chapters, it will force the protagonist to complete some tasks, such as maintaining his character setting. Later, the protagonist will put it in its place, because our Hiruma is pretty badass.

Theme: After the storm comes the rainbow