The trick here is I'm talking about something low-level, something the PCs should by all accounts be able to squash in a heartbeat...but it keeps escaping. Every time. And no matter how elaborate they get with traps and attacks, it keeps worming free and showing up again later.
I'm worried a set of encounters like the above takes away too much player agency, but as a storytelling element it would all be in good fun. Does anyone have experience with this sort of "gimmick fight"? Was it fun or frustrating for you every time their smug little face popped onto the playing field?
Context
The first ever fight my group (two people with limited D&D experience) had went terribly, terribly wrong. It was also my first time GMing, and I had thrown them against two bugbears and misjudged how much damage they were going to do. It ended up feeling like a seventeen hour fight with pool noodles for how little actual bloodshed there was, and eventually one of the two bugbears threw his buddy in the line of fire and used his body to escape. Hilarious at the time, and a good story we bring up constantly as a joke any time anyone starts rolling poorly.
Extrapolating from that, I think it'd be equally hilarious to have a (very) occasional fight against bugbears that the PCs are pretty much guaranteed to lose. No deaths, just a set of cowardly foes who refuse to hang around long enough to get their rear ends handed to them and choose instead to book it as soon as the going gets tough.
Obviously from my perspective this seems like a super funny in-joke, but I don't want to annoy my players, so I'm looking for anyone with experience of a similar scenario.
In answer to the comments; We're a rp-heavy group, both players are 4th level dual-classing (4/1 splits), and as a group we've only been playing together about 8 weeks. The tone of the game is generally fairly midline between humor and seriousness - we break character a lot to laugh and there's been plenty of in-character jokes too, but when the moment calls for it we can buckle down and get gritty. Most encounters right now are either easy wipe-the-table roadblocks, or semi-challenging encounters that require strategy but don't typically knock the PCs unconscious. The bugbears - if in the right number and with a terrain advantage - could probably do significant damage to the party, but there's functionally zero risk of a TPK.