Usually, reality TV hosts serve as impartial observers/occasional referees while overseeing reunion episodes.

But Nick and Vanessa Lachey chose to go a different route, and they might be regretting that decision these days.

If you watched Love Is Blind Season 2 then you're well aware that Shake Chatterjee is a massive douche who got what was coming to him on the reunion show.

But perhaps Nick and Vanessa should have let the cast tend to the matter themselves, because now Nick is getting dragged into the sort of petty D-list beef that he would probably prefer to avoid at this stage in his career.

The feud between Nick and his unexpected rival started when Shake called Lachey a "twat" in a recent social media tirade.

Chatterjee's comments came in response to harsh words that both Nick and Vanessa directed at the Chicago-based veterinarian.

Some viewers applauded the Lacheys for laying down the law, while others thought it was a little strange for the hosts to be raising their voices and dropping f-bombs.

Shake is firmly in the latter camp, and he's been firing off criticisms of Nick ever since the reunion aired.

(Vanessa has been immune to Shake's criticism -- more on that later.)

Chatterjee's anti-Lachey campaign continued on Monday when Shake posted a clip from Nick's 2003-2005 MTV series The Newlyweds.

For our younger readers, the show focused on Nick's marriage to Jessica Simpson, and it was quite the phenomenon at the time.

Of course, it's not the sort of show that one frequently revisits in reruns, which is good thing for Nick, as some of his behavior arguably hasn't aged very well.

“Sound on,” Shake wrote in an Instagram Story posted on Monday.

“@NickLachey not even opening the car door for his wife. Sad.”

The clip showed Nick refusing to unlock the car door for Jessica.

“At the beginning of our marriage, you were so eager to open the door for me,” Simpson said. 

“That’s because at the beginning of our marriage I got laid," Lachey shot back.

If that's the worst example of Nick's behavior that Shake could find, then his case is pretty weak.

But we're sure he'll continue disparaging Lachey regardless.

“You put a doctor on the show… of course you were going to see some critical thinking,” Chatterjee wrote on Instagram on March 7.

“Speaking of which, @nicklachey you’re a massive twat for your comment dragging vets. You do realize that becoming a veterinarian considerably more difficult than becoming a human doc right?

"Also consider learning how to be an impartial host before the season 3 reunion airs. Sorry I didn’t play along with your narrative like the rest of these puppets. Say hi to @vanessalachey for me.”

Say what you will about Shake, the man is nothing if not honest.

He copped to being attracted to Vanessa on the reunion show, and according to his ex-fiancee, Deepti Vempati, he made no effort to hide that attraction during filming.

“Can I tell you, he was hitting on her at the couples reveal,” Deepti said during a March 8 podcast interview.

“It’s so disrespectful.”

Yeah, Disrespectful is pretty much Shake's middle name.

But fortunately for Deepti, the man is Nick's problem now!