Activation text is: varesa
Her default outfit can appear with varying results using: defaultoutfit
If you want to control the different aspects of her default look, you can use (or not): crop top, detached sleeves, miniskirt
If you want to make it more likely her tail appears, add: cow tail
Some models get her eyes right, but if that's not the case, you can run inpaint with ADetailer and the following prompts: purple eyes, white pupils
Recommended to add to negative prompt: black pupils
Bonus! You can summon her mask with: masquerade mask, glowing eyes
In my experiments, the best Weight has been 0.8, YMMV depending on the checkpoints you use. For compatible checkpoints and example prompts, please check the sample images.
Let me know in the comments if you like it, I might try to improve it in the future.