To remove your ID from someone else's list simply download DaB (Deny a Buddy) from
Trolling_Around. Once downloaded follow these steps:
1. Enter Your yahoo id
2. Enter Your password
3. Then next to Targets ID enter the screen name of the person whose messenger list you'd like to be removed from.
4. (Optional) Change the Rejection Message to anything you want (example: "I don't want you on my list")
5. (Optional) You may check off the "Tick to iggy Target" to put that person on ignore.
6. Hit Action! and you have successfully removed yourself off that person's list.
The person will get the rejection message next time they log in if you are using version 7.0 and higher. (If you are using a lower version, which is rare since Yahoo! is dropping support of older versions, then they will not receive a message IF they are off-line.)