My Journey of playing Fate: Grand Order

Servants who has yandere tendencies or completely yandere

Shuten Douji

- Hates Ibaraki and Raikou
- Calls you her "husband"

Kiyohime

- Loves you dearly
- Lie to her once and you will transform into burned corpse in a spark
- Wants your babies

Mashu

- Calls you Senpai
- Doesn't want to be forgotten

Brynhildr

- Quiet but deadly
- Thinks you are Sigurd or his reincarnation

Ushiwakamaru

- Wants your attention focused only on her
- Can be seen her yandere personality on Onigashima event

Jack the Ripper

- Calls you "Mother" whatever is your gender
- Will cut your limbs if she finds you hugging another child

Serenity of the Hassan (Am I right?)

- Poisonous to everyone except you
- Craves for your touch

Artoria Pendragon (Lancer Alter)

- She stabbed Shirou once in a comic
- Why would she wear flashy costume if she isn't a yandere

Jeanne D' Arc (Alter)

- Her creepy laugh is an evidence
- Acts like a tsundere to get you to notice her
- She can be a yandere if she wants to

Minamoto no Raikou (Mami go away 😱)

- Treats you like her own child
- Can kill you by hugging her because of her humungous boobs
- Has tendency to rape you at night you aren't alert or you're drunk

Credits to Astaroth-Origin for informing me these servants who has yandere tendencies or completely yandere.