The video is the battle between Vegito and merged Zamasu. The beginning of the chapter is just the battle in writing style. Near the end of it is where things change...

In Future Trunks time...

The fierce battle had started between Vegito, Goku and Vegeta's fusion using the Potara earrings, and merged Zamasu.  

Vegito: Come on. What do you say we wrap this up.

Trunks (thinking to himself): So that's what Father and Goku look like fused together. Their energy is incredible!

Zamasu meanwhile only laughs as he makes a speech about mortal sins. Vegito who was tired of listening to him comes and delivers a punch to his face followed by a kick sending him away.

Vegito: Hah! Sorry to be rude, but I was tired of hearing you preach. Now come on! If want us to bow down to you then you have to use force.

Zamasu got back up.

Zamasu: Enough you foolish mortal. Now die!

Zamasu charges at Vegito who is able to dodge but teleports behind Vegito and delivers a swift punch that sends the fusion flying. The Saiyan though recovers quickly as he charges at Zamasu. The two proceeded to deliver a series of punches and kicks  before Vegito delivers a kick to Zamasu's face. The Saiyan fusion then grabbed him by the face and crushes him down to the ground.

Vegito mocks Zamasu.

Vegito: What's the matter? Where did all that power you were boasting about go?

Zamasu: I've had enough of your arrogance!

Zamasu power explodes as it sends Vegito back. The merged Zamasu reels back his right arm as Vegito does the same with his left.

The two collide creating a powerful force as the ground around them starts to come up. What the two failed to notice was a portal open up under them.

The two delievered swift punches and kicks before Zamasu manages to get a good hit on the Saiyan fusion as he smashes him towards the ground below. This is where things change.

Instead of being on the ground (Like what originally happened in the show) the fused warrior is thrown into the portal that was a result of him and Zamasu's epic clash.

Zamasu: What is this?

Vegito: Uh oh.

The Saiyan didn't have time to react as he fell in. The portal closed immediately after he went in.

Trunks along with past Bulma, Mai, Supreme Kai, and Gowasu looked on in shock as the portal that seemingly came out of no where sucked in their last hope to win the fight.

Trunks: What the?!

Bulma: W-What was that. What was that!

Bulma shouted at the two Kai's who reeled back.

Supreme Kai: I-I don't know! Gowasu, did you know what that strange portal was? 

The Kai of Universe 10 put his hand on his chin thinking.

Gowasu: The most likely reason the portal opened is the clash between the two.

Trunks: So your saying that the force created by them was so strong that it caused a portal to open?

Gowasu: That's the best I can come up with. It also seems like the most reasonable.

Trunks: Wait, are you saying there was another reason?

Gowasu: Yes, but it seems highly unlikely that it would happen.

Bulma: Well don't leave us in the dark, tell us!

Gowasu: Yes, right. My other theory is that someone must have opened a portal from somewhere.

Trunks: But who would do that? 

Gowasu: Not many could do it, so a god would have to create it. 

Trunks: But that can't be possible! Zamasu killed the god of this time.

Gowasu: That is right. That's why I'm leaning more towards the first theory.

Trunks: Your most likely right, but where did it end up taking Vegito?

Zamasu: That would be the least of your worries Trunks. Now that pest is out of the way, it's time for you and your filthy world to perish!

Trunks: Not a chance Zamasu! As long as I'm still standing, there's still hope!

Zamasu: While I admire your bravery, your a fool to think you can defeat me!

Trunks: Kai! Get mother and Mai to a safe place. 

Supreme Kai: Right.

Trunks: And one more thing, if I don't make it out of this, promise me you'll get them out of this wasteland...

Both Kai's plus Bulma and Mai looked shocked at hearing this.

Mai: What are you saying Trunks, of course you'll get out this alive!

Bulma: That's right sweetie, now go kick that guys ass!

Trunks smiled at his mothers words.

Trunks: You got it.

Gowasu: I wish you the best of luck young Saiyan...

Supreme: Yes...

Trunks nods his head as the Kai's took both women to a safer spot to watch the battle.

Zamasu: How touching, now, prepare to meet you end mortal!

Trunks transformed into his rage form.

Trunks: Funny, I was about to say the same thing!

The two charged towards each other. 

Meanwhile the Kai's set down Bulma and Mai as they watched the battle unfold.

Mai: Trunks...please come back to us.

Supreme Kai: Hopefully Trunks has enough to put an end to this.

Gowasu: Yes, I fear if he falls then we don't stand a chance against Zamasu.

Mai: He'll win, I'm sure of it!

Bulma (thoughts): Goku, Vegeta...where did you go...?

Oops! Didn't expect a new story did ya? I was just thinking of possible stories to do and I actually did a roll where I put every anime in and rolled to see which would be a crossover with DBS. Out of everything dxd came up. I love me a good crossover so get ready when next time Vegito lands in the world of dxd! See ya next time folks!