well that's make sense and i also don't know if she is just naive or stupid
I think both Emma and Suzi are both immature, just in different ways. They were highly sheltered by a woman who was attacked by and is highly distrustful of men, so it has affected them negatively. Suzi is just old enough to remember their father, so she's grown to be more spiteful and took on the protector role, but that really kind of isolates Emma even more. Emma is just immature in the naive way - she takes everything said to her literally and thinks everyone is well-intentioned and nice by default, which kind of blinds her to the spitefulness of others, which everyone has in a great amount especially in the setting of Hillside.
just ask but is Emma ugly? or those NPC have to act and say that she is ugly and bully her ?
The anonymously texting was just a way of emotionally manipulating her by feeding her insecurities, and then he would follow up by negging her once he set his plan in motion. Negging is just another way of emotionally manipulation by mostly using backhanded compliments, like "I don't think you're that fat/ugly." That implies he still thinks she's fat/ugly, just not enough to insult her, and since it's coming from someone she greatly admires, she sees it as a compliment. She's not an ugly girl, just very very insecure. And she was also attacked once herself prior to the events of the game which has affected her mindset as well. I don't remember what the specifics of the attack were offhand, but it's why she wears the jumpers & jeans all the time in the beginning.