How do I create a 'write on' effect?

Hello,

Say I had an image of some text that spelt 'TOM' - is there anyway I could animate a mask that makes it look like the image is written on?

My logic is coming from doing the same thing in after effects but I'm aware edge animate is very different.

Please let me know if there are anyways of creating a 'write on' effect.

Thanks!

Tom