How do i wipe someone completely from my sl and wipe my self from theirs?

[Alaura Silverfall]

How would I become invisible to one person and have them invisible to me so i can go to my same places without either one of us having any knowlegde of the others presence?

[Alwin Alcott]

the only thing you can do is mute/block, and derender

but it will never wipe somebody out, the person will always be able to see you (if not derendered mutual)

and you will always be seen on minimap and radar

[Rolig Loon]

That is impossible.  It is a simple matter to write LSL scripts that can tell you who is in the same region that you are in, and (as Alwin pointed out) your miniMap offers that information directly.  It is also extremely easy to write a LSL script that will tell you whether a specific person is in world or not, although it won't tell you where the person is.  When you enter a social world like SL (or RL), you should know that it is never possible to be totally invisible. The best you can do is ignore and avoid people you would rather not see.