It depends. If the portrayal of the yandere girlfriend is done in an interesting and nuanced way, it could be appealing. But if it's overly stereotypical or one-dimensional, then no.
A gift from her in a yandere manga can have multiple meanings. It could be a sign of the yandere's obsessive love, an attempt to control the situation, or a way to create drama and tension in the story. Sometimes, it might even be a red herring to mislead the reader.
Male yandere characters in stories are often overly possessive. They have an intense and sometimes obsessive love for the object of their affection. For example, they might not allow their loved one to have any other friends or interact with others freely.
The following are some examples of anime or manga where the male lead is extremely possessive:
1 Sebastian Michalis in The Black Deacon: He had a strong possessiveness towards Shire, even going against his principles and morals.
2. Kimki Ken in Tokyo Ghoul: He has a strong possessiveness towards his goals and the people around him. He protects them at all costs.
3 Naruto Uzumaki in Naruto: He is a person who is extremely eager to get recognition and a sense of belonging. He is very possessive of Sasuke.
4. Inuyasha in Inuyasha: He has a strong possessiveness towards Kagome, even using violence and controlling means.
5 Wei WuXian in "The Founder of the Demon Path": He has a strong possessiveness towards Lan Lan Xian and others, sometimes even showing violent behavior.
If the male protagonist was a monster, the story would usually involve the relationship between the monster and humans. These stories might tell how the male protagonist fights monsters and how he finds a balance between humans and monsters. These stories might also tell how the male protagonist gained the trust of humans and helped them fight against monsters. In short, manga with a monster as the male protagonist usually involved a lot of complicated plots and character relationships.
The following are some examples of anime or manga where the male lead is extremely possessive:
1. Kim Mu-yan of Tokyo Ghoul
2. Alan Yaeger, The Attacking Giant
One Piece: Monchi D. Luffy
4 Naruto Uzumaki Naruto
5 Detective Conan, Far Mountain and Leaves
6 Inuyasha
7 "Death" Xu Yuanxuan
Silver Soul, Songyang
9 The Prince of Tennis, Atobe Keigo
Naruto Stormy Legend Uzumaki Naruto
I hope the above answers can help.