I use Staedtler Lumocolor 315 pens (fine and medium).
WARNING they come in permanent and non-permanent versions! Be sure to
get the latter. The only difference between the two is the lettering
along the side of the pen.
They don't rub off easily but will come off with an eraser or
'baby-wipes'
(tissues damped with alcohol)
I've used them for layouts for custom paint jobs on many different
plastics and acrylic surfaces, but test on a non-critical area first.
Available from most arts and craft shops here (UK)

Denis
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DT
Replace nospam with the antithesis of hills