Tired of companions that are always hanging on, talking the same routine over and over? Do you want to go solo with a little help now and then? The lurking followers will travel with you but they keep their distance and don't interact. No more endless talk. They leave  you alone and usually stay in the background but join the fight when they're around.

Sledge: Slow and steady and heavily armored. Attacks with a power hammer.
Calamity: The blind sniper, moves faster than Sledge but lurks further in the background. Her cat sees for her.
Daisy: Mutant hound. She'll run to you, stay close, charge your opponents.
Swarm: A posse of four stingwings inflict poison damage on your enemies.

Note: the lurking followers don't behave like true companions. There's an element of uncertainty in their behavior. They don't travel together, and sometimes you'll lose them. Sometimes you'll have to fend for yourself. But eventually they find you again. They'll usually fast-travel if you do and will show up in Far Harbor if you go there. When you go indoors, they may take a minute to follow you. In other words, don't depend on them to always be there to save your hide.

Backstory: When the alien spaceship crashed near Oberland, some captive shapeshift entities on board escaped and took on material forms
and for
some reason known only to the gods of mods  decided to follow you around. Because they materialize at the alien crash site at install, they may take time to reach you depending on your location at the time. Swarm arrives fast enough, but Sledge only walks and might take a little longer to reach you.

Note: This is a FOMOD install, which means you can choose as many followers as you want during install. BTW: they won't replace your usual companions.