stheno/ステンノ/斯忒诺 (Fate/Grand Order)

The trigger word is stheno_fgo, and the recommended tags are best quality, masterpiece, highres, solo, {stheno_fgo:1.15}, long_hair, twintails, purple_hair, hairband, purple_eyes, lolita_hairband, smile, very_long_hair, jewelry, bangs

https://civitai.com/models/197512/stheno-fategrand-order