Imma just be honest with you. You are clinging onto broad things. Pink hair, that’s pretty broad right? Now is pink hair that is tied up into two sections and let down with a heart shaped hair sticking up in the middle broad? I don’t think so that is rather specific. Now combine that with those two other things you said and try to analyze her artwork and style again. Everybody is different and has different ideas, which would mean that artworks shouldn’t be similar. Yet again there are so much people in the world that similarities in artwork will occasionally happen, but they shouldn’t be so similar that they embody all of her oc’s specific elements of those broad terms you used.