macOS quick applescript question

Essentially I want to write an applescript that would make one program open, AND close when another predetermined app is opened and closed. Basically I want the app "Bowtie" to open when iTunes opens, and close when iTunes Closes. I've never scripted in apple before so i'm a bit of a noob at this.

Alright how about this. Is it possible to run a command in applescript that I can set to run when my computer starts, that just waits for iTunes to open, and when it does it tells the bowtie app to open? like... something like this

tell application "Bowtie'
activate
when application "itunes" activates
end tell

I know that's a totally ridiculous way of writing it, but you get the point. I know applescripts just run once and done, at least as far as i know, so to my knowledge there isn't any way to have this script continuously running in the background waiting, if there is, AWESOME someone please enlighten me, if not, perhaps a command at the end of the script to run itself again?