That checks out, Billy then attempts to grapple you, make a strength saving throw with advantage because Billy is weak. Also if you succeed you still have an action to do stuff.

16 and I will use Abi-Dalzim's Horrid Wilting on Billy

You throw Billy off you and then Billy rolled a 4 for the save so he takes 46 damage, problem is Airsenhite got caught up in the square and takes 23 damage due to passing the check and is incapacitated as Billy starts writhing on the floor from the spell.

I will heal both of you and run of to hide again 

Airsenhite heal 20

Billy heal 16

Okay, Billy is still doing kinda bad but is better and Airsenhite is back up and no longer barely living, Airsenhite curses in infernal before asking Billy if he saw where you went. Make a stealth check.

20

You are very stealthily hidden and Airsenhite nor Billy can find you when they search for you.

Severon is going to smirk and have his eye glow purple

2 very strange looking bats then attack Airsenhite and Billy and they run off and then you hear 2 gunshots before you see them come running back and continue looking for you.

Airsenhite finds you and casts his wand on you, make a constitution saving throw.

19

Well the first roll you did says 4 so you fail the check and you are now paralyzed for 1 minute, Billy rushes over to you, takes out some holy water and casts protection from good and evil on you.

Severon starts to steam as the holy water touches him

After one minute you become un-paralyzed  and Billy is still concentrating the spell on you, you are protected from good and evil (basically celestials, fiends, elementals and abbrations.)

Severon will jump up and start running away

"Severon wait!" Airsenhite yells but decides to stay back and not chase after him.

Severon is going to climb the tree again

constitution saving throw please after climbing 10 feet.

NVM then

Severon is going to make camp so he can sleep