TwinstarDragon: Thanks for the suggestions.

Sea Dungeon

Dagobah Municipal Beach Park

Musutafu, Japan

"Uggh..." Ochako groans as she rubs her head, dusting off the sand sticking in her hair, and sea shells around her.

"Where am I?" Ochako looked around and could only see a dark cave with a heavy scent of the ocean from everywhere. Ochako flinched a bit when she felt a droplet fall into her hair.

"Okay, Ochako...let's take a few steps back. I was near the sea collecting sea shells for our sand castles, then suddenly, seawater starts to swirl up and a portal emerges, and I got sucked in." Ochako says before she blinks at what she just said. "Wait, portal? Is this caused by someone's quirk!?"

She turned around and saw a red portal behind her, causing her to let out a sigh of relief. She gets up before trying to walk towards it but she ends up bumping her head. She groans in pain, feeling like she has just bumped into a brick wall.

"W-what!?!?" Ochako asks in disbelief before she starts touching the portal again, but it is like there's an invisible wall in there. "Oh great, it's blocked!?! Why is there a portal anyway?!?"

Ochako groans incredulously before looking around. She can feel goosebumps crawling into her skin.

"...maybe there's another way out...?" Ochako mutters before shaking her head. "No, no, I don't think I can go. The place was just too dark, and this is the only portal I know." She sighs. "I hope Izuku and Eijirou notice I'm gone and go find help..."

Ochako blinked when she heard an unfamiliar noise, like the sound of water bubbling. She turned around and saw a water orb gathering at the top of her head.

"Wha-!?" She didn't get a chance to finish her questions as the water suddenly bent and shot toward Ochako's right leg, piercing through it and drawing a lot of blood. Ochako's eyes widen before she screams in pain, clutching to her wound.

Ochako shivers when she hears a cackle from the shadow as slowly, a figure emerges from it. Her eyes went wider as the figure revealed to be a woman with pale blue skin, hair made out of water, seaweed, and fish nets covering her body like a dress, with some of the fish nets covering her face like a bride.

Ochako shivers as the woman opens her eyes, revealing black sclera and iris, her mouth grinning widely, showing coral-infested teeth. Ochako saw the woman extend her hand, revealing a skinny pale hands with fish bones on her fingers like claws, as water gathered around her hand. Ochako's eyes widen before she scrambles away from her, barely dodging an incoming water bullet that scratches her thighs.

She gets up before she slaps the woman, but she widens her eyes as her quirk did not affect that woman before two water bullets pierced through her hand as she screamed in pain and falls over. Ochako starts limping away as the woman slowly turns her face towards her, still showing her black eyes and sharp teeth, giggling like a maniac. Ochako's eyes slowly get moist as she continues to limp.

'S-somebody...help...' Ochako thought in fear as she had just witnessed a woman who no-sell her quirk without doing anything.

Outside the Dungeon

"Graah!" Eijirou, in his Were-Liger form, strikes the red portal with his fist, only for an invisible barrier to deflect his attack. "Damn it! We can't get in there!"

"This shouldn't be possible..." Izuku mutters in disbelief. "When we try to tail Lady Nagant, this kind of thing didn't happen. So, what makes it different!?"

"Well, first of all, the portal's red instead of the usual blue." Eijirou growls. "If I recall, this kind of discussion was once mentioned by Edgeshot and he explained to us about it, didn't he?"

"Oh, yeah! Edgeshot once explained this, the Red Gate." Izuku slams his fist into his palm. "It's a special case of the gate where it seals off the entrance after someone enters it, and the monsters inside it are far stronger!" Both boys stayed silent before they went panicking. "Shit!!!"

"Fuck!!" Eijirou panicked. "And Ochako was alone in there, trapped!"

"Shit, shit, shit..." Izuku mutters before he places his hand on the gate. "Come on... there must be something...a way to get into it." Suddenly, a notification window pops up, causing Izuku to blink owlishly.

[Mission: Save Your Mistress]

[Your future wife has gotten herself trapped in a Red Gate. Safe her before it was too late!]

[Time before her impending doom: 00:21:37]

[Warning: Once you accept, the Red Gate will temporarily open. You can only enter alone!]

[Rewards: 1 Random Rune Stone]

"..." Izuku clenches his fist tightly, annoyed by the fact that even the system teases him about Ochako. But, his annoyance was immediately replaced by anger, unable to believe that the system treating this like a game.

...well, everything seems to be taken from the game, but that's beside the point!

"Ei...I found a way to get into the portal." Izuku says, getting Eijirou's attention.

"That's great!" Eijirou says in relief. "Let's go!"

"Unfortunately, only I can get in," Izuku says before looking at Eijirou, who frowns at him. "I don't have a choice. The system made this condition."

"...I guess I can try to find a way to contact Gang Orca..." Eijirou mutters before facepalming. "I wish we didn't put our phone back at the apartment..."

"Yeah...that was my mistake," Izuku mutters. "I was hoping for a normal day off."

"I was hoping for one as well," Eijirou says with a snort. "Go save her. And be careful. You may have the system, but you're not immortal."

"Yeah, I know," Izuku says with a smile. "I rather not experience death again." Both boys shiver before looking at each other. "Wish me luck."

"Yeah, of course." Eijirou bumps his fist on Izuku's chest as Izuku smiles before looking at the portal.

"[Accept Mission]!" As he says that, blue lightning surges from Izuku's hand and into the portal as cracks start to appear around the gate before it shatters. Izuku immediately rushes into the portal with [Quicksilver] as the cracks are repaired in less than a second.

"He wasn't kidding when he says that only he can enter. I can't even go that fast." Eijirou mutters. "Now, time to go back to the apartment to contact Gang Orca..."

Inside the Dungeon

Izuku lands on the ground with a 'splat', mud covers his feet but he pays no mind. He is more focused on the smell of blood blending in with the smell of the ocean. He looked down and froze as he saw a trail of blood on the ground from the entrance to his left.

Izuku is silent as his hand trembles in rage as his ears pick up noises from the shadows. A notification window pops up and shows Izuku a timer.

[00:19:59]

"...I have no time to deal with cannon fodders..." Izuku mutters as he turns his face towards an army of monsters emerging from the shadow. The monster resembles a short humanoid reptile with a pair of webbed feet and hands, a turtle shell on its back, and a beak instead of a mouth.

Izuku faces them as green pixels start to cover his hand and slowly extend before they dissipate, revealing a familiar black lance on Izuku's hand, the [Black Crusader] .

"You monsters are in my way," Izuku says as he takes a stance before activating [Mana Coat] and [Quicksilver]. "Now, perish."

In a blur, Izuku blitzed through the monsters like a bullet train, letting out a powerful sonic boom as bloods exploded from the monster he passed through before it rained down. He turns off the [Mana Coat] before continuing to use [Quicksilver] to go after Ochako.

"Hang in there, Ochako," Izuku mutters as he continues to blitz through hordes of monsters and monsters. "Don't die on me..."

With Ochako

Ochako pants tiredly as she leans onto the wall, clutching her leg and hand with visible gaping holes in it. She grits her teeth in pain before she takes off her clothes, rips them off, atisatisfiesem around her wounds, applying pressure on them.

"I...I should've...done this earlier...but...then again, that woman is ruthless..." Ochako mutters as she tightens her makeshift bandage before letting out a sigh. She hears a familiar voice before ducking away, barely dodging a water bullet flying past her. Ochako covers her mouth, panting heavily as she hears another manic cackle from the other side.

"D-damn it..." Ochako mutters in frustration as she hears the cackle gets louder. She felt her heart beat faster and faster, her body shook in fear. "W-what should I do...?"

To be continued