My OP Minion System in the Apocalypse

"Rein Alchemilla."

Suddenly, grass appeared on the previously dull, rough stone floor. It was a bright green, in complete contrast to the dark, grey colouring of the cave. Both of them stepped into the soft grass; they raised their weapons in anticipation of the upcoming battle.

"You know~ we don't have to do this, I wouldn't mind making you one of my offspring... after you apologise for what you did to Celeste."

"Shut up bloodsucker, I hate annoying things, and you're annoying me."

"Aw, that wasn't very nice, we could be friends, you know~"

Robbie held out his hand.

"Rein Helleborus."

A flurry of vines was extruded from his palm. They travelled straight towards Lest, however, it didn't seem that he was the least concerned.

With one swift movement, he managed to slice every single vine with his dark red blade. A reddish aura was left in the air, in the trail of his swing. The strong vines were all sent crashing into the ground.

"You're a Duke, aren't you."

"Whatever do you mean~"

"I came prepared for this."

Suddenly, Robbie summoned a potion from his inventory and popped off the lid. A green liquid fell down his throat as he consumed it in less than a second.

"You've got a potion, is that your plan to defeat me?"

"Yes."

"Aren't you underestimating me a little?"

Robbie's expression changed.

"Renisa Helleborus!"

Another wave of vines was summoned from his arms. However, this time they were surrounded by a greyish tint. They were also thicker than usual, looking a little like malleable metal poles.

Lest raised his sword again. Just as the vines were about to latch onto his, he swung his sword incredibly quickly, connecting with every single vine. There was a slight bang before all of the vines were knocked away. However, this time, the vines didn't fall to the ground, instead, they began moving towards his again.

Swinging his sword, he continued to keep the vines away, smacking them every once in a while. No matter how many times his blades cut the vines, they just kept coming.

"I see now."

A dense red aura concentrated around Lest.

"Sword, drink my blood."

The aura exploded around his body, forming a bright red ball of light. As Lest's blood dripped down to his blade, Robbie took a step back. Swiftly, Lest cut every single vine, his blade pierced straight through the fibres of the strengthened vines. A moment later, the vines fell to the ground, slowly withering away.

"Y-you... even managed to break those...?"

"Eh? Don't tell me that was all you got."

A smile formed on Lest's face.

"Come on, show me more~"

With no other choice, Robbie raised his sword.

"Nija, give me more power, as much as you can."

With that, the spirit of a young girl appeared in front of him. She was invisible to Lest, however, he continued to wait for Robbie to do something.

'Ah, you're in a situation aren't you."

"Please hurry."

'Alright, I'll be taking some of your lifespan, are you sure about this?'

"Yes, do it."

With that, she vanished back into thin air. More power circulated through Robbie's body as he braced himself to attack Lest again. Dashing at Lest, he swung his sword at him.

Their swords clashed as Lest blocked his attacks without much issue. Robbie planted his feet into the ground and swung his sword as quickly as possible, trying to break through Lest's defences. However, it was clear that he wasn't making much progress.

"Let's go, Nija."

All of a sudden, he teleported behind Lest. Catching him completely off-guard, he managed to land a very powerful strike on his back. His blade sliced through the vampire's clothes, cutting right through his skin, flesh and bone.

Lest swung his blade around, trying to catch Robbie, but with the help of some vines, he managed to dodge Lest's attack. After a short moment, the wounds on Lest's back began healing back up, becoming as good as new within a few seconds.

"Damn... I can't get through that regeneration..."

"Aha~ that teleportation trick really surprised me."

Slowly, Lest began walking toward Robbie.

With his long crimson blade raised in front of his, he unleashed a wide swing. Robbie managed to block it with [Nija-T'an-Mo] but just the impact forced him off of his feet. Next, Lest lifted his leg, caught off-balance, Robbie couldn't do anything against it. Lest's foot smashed into Robbie's stomach, sending him crashing to the ground, gasping for air.

Using vines which were protruding from the walls, he pulled himself away, coughing and gasping. As he gained full awareness of his surroundings, he felt another impact on his side. He was launched off of his feet, smashing into the rough side wall of the cave.

"Come on, aren't you going to show me any more tricks?"

"Shit..."

Without hesitation, Lest grabbed him by the collar and slammed into the rock wall again. Rubble and debris began raining down as the impact caused a large dent in the side. A severely-wounded Robbie looked up at the vampire.

There was blood dripping from his arms and legs.

"Ah, have you finally decided that you've lost?"

"...l-let's go... Nija."

"Huh?"

Robbie suddenly vanished from Lest's sight.

"Renisa Helleborus!!"

A huge wave of vines was conjured from Robbie's palm. He was only a few centimetres behind Lest; the vines needed to only travel a tiny distance before they were able to clutch onto Lest, rendering him immobilised.

However, Lest wasn't fazed.

He simply turned around and swung his blade, launching a huge red shockwave into the air. It crashed into the vines, causing them to separate from each other. Right after, Lest cut through every single one with his crimson blade.

A moment later, the vines all fell to the ground.

"Nice trick, you almost got me there~"

Without even enough energy to continue standing, Robbie fell to the ground.

"Oh well, you'll make a nice offspring."

Lest started walking over to Robbie.

Picking him up by the neck, Lest brought him closer to his jaws.