The Swift Thunder party had been inside the boss room for a while now. Along with Lilith and the others, I was waiting outside for their battle to conclude, but so far, there hadn't been any cries for help or screams.

"!!"

Suddenly, my Danger Sense skill reacted. One of the members inside the boss room had been injured, and it seemed to be a fairly serious wound.

"...Excuse me. One of the Swift Thunder members is hurt, so I'm going in to assist. You all stay here. Entering a boss room during battle is considered a violation of adventurer etiquette, but I'm not an adventurer, so it doesn't apply to me."

"Hey, Masayoshi!"

"Master Masayoshi!"

I ignored Lilith and the others trying to stop me and entered the boss room. Even if it's considered a problem among adventurers, I'm not one of them, so it doesn’t matter. If they try to accuse me of something, I can just run away if necessary.

A memory of a traffic accident in Japan suddenly surfaced in my mind. Even if I had inherited the power of a Great Mage, I couldn't bring back the dead.

I briefly saw the bloodied body of a person being pulled out of a car by the rescue team. Even though I knew there was nothing I could do, I still felt a bit powerless. Even if it's just for my own satisfaction, if there's someone injured right in front of me, I want to help them.

"I'm here to assist! I'll heal the wounded—"

Scuttle scuttle scuttle scuttle

"Gyaaaaaahhh!!"

W-Wait, what the hell?! No way! Gross, gross, gross!!

I almost reflexively unleashed an extreme-level magic spell despite being inside an underground dungeon!

This was completely unexpected! No, considering the kind of creatures that had been appearing in this dungeon, I suppose it shouldn’t be surprising that these things showed up!

The final boss of this dungeon was...

Countless... Cockroaches.

...Yeah, I know what you're thinking—why is a high school guy screaming over cockroaches? But no, this is different! This is bad!

Black and brown cockroaches, each around a meter long, were scuttling at high speed, swarming the Swift Thunder party.

Sure, I've seen cockroaches back home before, but not at this size, and certainly not moving in a coordinated mass like this! This was an abomination!

Rats, moths, spiders—those I could handle, even if they were oversized. But these things? No way. My body instinctively rejected them.

"Hey, you bastard! Who said you could just barge in here?!"

"This is our fight! Get the hell out!"

Watching them fight brought me back to my senses a little. The boss room was bigger than I expected, and between them and the entrance, there was a writhing mass of cockroaches blocking the way. Had they been pushed back while fighting?

Three of them were holding the front line, defending their fallen comrade while fending off the swarm’s relentless assault.

Even in this situation, they still had the nerve to yell at me. Whatever, I'm helping for my own sake.

But I had a problem—I needed to get closer to heal the injured, but that meant passing through the ocean of cockroaches. Damn it, I need to hurry!

"Hoo!"

"Fūsuke?!"

Suddenly, Fūsuke, who had been perched on my shoulder, took off into the air, flying past the cockroaches and reaching the Swift Thunder party.

Wait... Why didn’t I think of that? I don’t need to go through them—I can fly over them! Sure, the cockroaches can fly too, but they were focused on the Swift Thunder members and me, so Fūsuke had slipped right through.

"Hoo! Hoo!!"

"Whoa! A barrier spell?!"

"Hey, what the hell do you think you’re doing?!"

Wait... Fūsuke can use magic?! I summoned him, but I had no idea! I’d never put him in battle before, so this was news to me!

A barrier had formed in front of them, blocking the cockroach swarm’s charge. Nice, just hold out a little longer!

Using wind magic, I created footholds in the air to leap over the cockroaches. …I mustn’t look down. What’s below me is probably more terrifying than looking down from the balcony of a high-rise apartment.

"Fūsuke, keep the barrier up for a bit! High Cure! High Heal!"

"Whoa! The poison’s disappearing, and the wounds are closing right before my eyes!"

"Y-You… You’re not just some baggage carrier?! You’re a high-level mage?!"

"Ugh… Uuh…"

Avoiding the cockroach horde, I managed to land near the Swift Thunder members and cast antidote and healing spells. Good, my Danger Sense skill had stopped reacting—they should be fine now. To make things worse, some of these cockroaches were poisonous.

"Do you know their weakness?"

"Ah, yeah. They’re not that tough—if you crush their heads, they stop moving. But they’re fast, there’s a lot of them, and some are poisonous, which makes them a huge pain."

I asked their leader, who was wielding a large axe. So crushing the head, huh… I had been avoiding looking at them too closely, but now I noticed there were already several crushed cockroach corpses scattered around.

...Even knowing their weak point, the idea of having to crush all these cockroach heads was mentally unbearable.

"Masayoshi, are you okay?!"

"Big brother!"

It seemed Lilith and the others had finally entered the boss room as well. Cockroaches... Cockroaches… I just wanted to end this nightmare as soon as possible.

I don’t know if this will work on otherworldly cockroaches, but let’s try ice magic!