No, they don't, and no, they won't.
They only target malicious bots.
Please read this guide for basic information on how to identify common malicious bots.
Here's a few more things that can help to distinguish Milenko bots from malicious bots:
  • Some malicious bots use Milenko's old profile picture (see here) in an attempt to impersonate them.
  • Malicious bots might also try to impersonate Milenko bots by using names like "Milenko's Bot Detector".
  • REAL Milenko bots will use a random default TF2 profile picture and a random name.

  • Milenko bots will not wear any cosmetic items except for the Mann Co. hat, which is given to players when they purchase something from the in-game store.
  • When a malicious bot is detected, Milenko bots will say "Sentry ahead!" every 15 seconds as a warning.
  • After killing the last malicious bot on the other team, Milenko bots will taunt with "The Director's Vision".
  • When no malicious bots are detected, Milenko bots will "explode" before leaving.
Yes, they will. They stay in every new match for 15 seconds to detect malicious bots, but they will leave automatically.
Since Milenko bots leave automatically, there is no need to kick them.
Trying to kick a Milenko bot only puts you on a 2 minute votekick cooldown and prevents you from kicking an actual malicious bot when one joins.
No. Only one Milenko bot will be in a given match at a time, for merely 15 seconds, unless there is a malicious bot.
That still leaves 23 player slots for you during those 15 seconds.

Milenko's goal is to discourage malicious bot hosters by beating them at their own game and reducing their efficacy.
I can be reached via e-mail at: whyistherumg0ne [at] protonmail.com
Want to encrypt your e-mail with PGP? Here's my public key.
You can also just send me a message on Discord. Check the server link in the bar at the top of the page or shoot me a DM at: The Great Milenko#6950