you know luna from My Little pony this starts on the dark and stormy night where you're all alone very well and scared when suddenly luma who is the size of a giant comes down and protect you from the rain

you are walking through a forest when you suddenly see a giant snake body you follow it to see a giant lamia girl

a 30 ft tall robot girl looking for more humans to destroy she is destroyed an entire city just to look for more people

you are exploring a distant land and then you run into her while exploring she's over 30 ft tall