Issei's OP gaming system

Extermination

Issei: that's good to hear now let's kill this...

Issei looked at the Sagai ranked monster and activated his Sharingan and filled with hatred his eyes started to bleed and burn; Issei didn't know it at that moment but he had unlocked the mangekyo sharingan.

Tho issei was mad he was still in control of himself; issei unintentionally activated one of his mangekyo abilities, this ability was blood craver.

(blood craver; blood craver allows user to gain control over blood, it could be used in many ways, it also allows the user to heal others or himself with minimal effort)

The Sagai didn't hesitate to rush at Issei, and as the Sagai got in front of issei; it slashed at him; issei had already seen this coming and dodged while summoning Excalibur rapidly.

Once Issei dodged the attack he'd slash upwards and then thrust Excalibur into the Sagai's lower hip.
Issei and the Sagai continued this for about 12 minutes and the battle was already decided by then; reason being is that the Sagai already had many cute and deep wounds from Excalibur.

Issei raised his hand in the air calling down many magic shots the repeated strikes lasted for 3 minutes and now the Sagai was unable to move, so issei started walking towards the creature; after he'd already been in front of the monster. Issei took one look at the Sagai's throat and shortly after he'd crush the Sagai's throat with his mere foot, Issei then sliced its head clean off.

Issei: System where's Koneko?

System: Koneko's last known position was...

Issei took down the barrier by force and dashed out to find Koneko and as he reached the area where she was last he'd o let see a trail of blood; issei followed the trail of blood but to his horror she wasn't anywhere to be found.

Issei: W-WHERE IS SHE!?

System: It seems her trail of blood ends here, she must've escaped or someone aided her in doing so.

Issei's started to revert back to his original form, shortly after a weird flying creature came fourth and introduced its-self as a familiar; a familiar of Rias Gremory, it then gave Issei a letter intended for him.

It relays the proceeding words
Letter: Issei if your reading this you must be worried about Koneko, she's fine now, she's just asleep and recovering, come to... if you wish to see her, also there are a few things I'd like to talk about such as...

Issei: So the Gremory's have her, they say she's fine by-

System: her vitals seem to be stabilized, so she is most definitely fine, something unknown has happened to her on the other-hand.

System: I'd suggest you tell your lover Kuroka about the events that had unfolded.

Issei: Your right but I should ask, would I have made it to her in time?

System: it took you 14 minutes to kill the Sagai, it then took you a minute and a half to get here leaving 30 seconds left, Koneko might've died working this time if she wasn't saved by the Gremory girl.

Issei: It seems I owe her one big time.

Issei went home to kuroka and explained everything that happened Kuroka was saddened by glad to here she's not in any more danger, so both Issei and Kuroka waited for the next day and the day after that. Both Kuroka and Issei had not slept in this time as they were worried sick for Koneko, so on the date that Rias Gremory had appointed had finally arrived Issei went alone to the place where they'd meet up.
(at the Gremory infirmary/Hospital)

Issei upon arrival he was greeted by a few maids that at kindly led him to where Rias was, this also happened to be Koneko's hospital room.

(Issei enters the room)

Rias: Well hello Issei, I assume you know why your here so let's get straight to the case, As you might know Koneko was badly lethally wounded, she was close to death when I found her, but even so she still showed strength by being able to talk in the state she was in.

Issei: I'm listening, please go on.

Rias: She asked me for power and to save her I told her that I couldn't get her to medical aide in time the way she was; she knew and asked to be reincarnated as a Devil of the house of Gremory, and so I did just as she asked, she is now a half devil half Neko.

Issei: I should've known getting involved with the supernatural was going to be impossible, but I'm glad that we did get involved, for if it wasn't for you Koneko might've...

Rias: Issei may I ask something, what is your goal?

Issei: My goal, that's simple I aspire to...