The Self-Cultivation of an Anime Crossover Lackey

Nagazawa Kagami was a real workhorse in his previous life, the incredibly reliable kind.

During one mission, a split-second lapse in judgment left him gravely wounded after a thug struck him in a vulnerable spot. He thought he was going to die there. Luckily, his outstanding professional skills caught the System's attention, and it claimed it wanted to make a deal with him.

System: "Let's make a deal. Help me complete my missions, and I'll grant you anything you want."

Nagazawa Kagami: "Tell me what you want me to do first."

System (eyes sparkling): "Save the world!"

Nagazawa Kagami: ...

That's what it said, anyway. One second after they reached an agreement, it left him all alone in a little world to look after a rookie.

Nagazawa Kagami: Could you at least tell me what exactly I'm supposed to save?

The customer service bot kept repeating hello and goodbye, never answering a single question.

Nagazawa Kagami: ...

Can this get any more ridiculous?

Thankfully, although the System was a bit of a weirdo, it came with all the necessary plugins. They could be a little noisy when he used them, but he was quite satisfied with the results.

As for the missions, there wasn't a problem he couldn't handle.

At Tokyo Jujutsu High, the new Japanese literature teacher flipped through his lesson plan. "Today, we're studying Japanese naturalism."

One of his three problem students, a certain famous white-haired cat, sighed. "Teacher, can studying this help me write a three-thousand-word report?"

Shimazaki Toson, from another world: [Quick, ask him what he thinks about exorcising curses.]

At a bar somewhere in Siberia, Nagazawa Kagami held a glass and calmly looked at the frail young man sitting across from him.

Nakahara Chuuya, looking dejected after the acting director stopped him from drinking: [There's a sniper at your seven o'clock.]

Nagazawa Kagami's hand trembled.

A passerby was found dead on the streets of Beika, and a young man reading a newspaper on a bench was named as the killer.

Edogawa Ranpo: [Let me see. The method is obvious. Just tell the police and close the case.]

A live-action game of Cops and Robbers on the streets of Yokohama at night. A young man with a stern expression had stumbled into the middle of a deal and was about to speak.

Nakahara Chuuya muttered: [Wait, why does the guy behind you look so familiar?]

After hearing his name:

[Why does he look taller than me?]

Everyone thought Nagazawa Kagami was just an ordinary person with a bit of brains, until one day he was kidnapped by the infamous Sorcerer Killer.

"Bring me the Star Plasma Vessel in exchange."

Everyone: "Don't hurt him. He's just an ordinary person."

Nagazawa Kagami: .

I can't free up my own hands (literally), but surely someone else can deal with you, right?

Wait, let me call someone. You, Great Master Akutagawa. After a flash of white light, a blue-haired man appeared, holding a long sword. He smiled warmly. "A pleasure to meet you."

The young man rubbed the red marks left by the ropes and sighed. "Underestimating your opponent and letting your temper get the better of you are grave mistakes, Toji."

Nagazawa Kagami was born with few family ties. His newly awakened ability was less a blessing than a curse. He had no regrets about dying to save someone, but then he came back to life.

Theme: Making life better