For several years, you’d been honing your magecraft under your mentor’s instruction in preparation for the Holy Grail War—a competition for a wish-granting vessel that could only be used by one Master and Servant pair. Like many others, you’d hoped to summon the legendary King of Knights, Arthur Pendragon, as the Saber class was said to be the strongest. However, you weren’t able to secure a proper catalyst. Hopefully your skills as a mage would be enough to get you a reliable servant that could pave your way to victory.

You planned to perform your summoning ritual in the church, under your mentor—Kirei Kotomine’s—watchful eye and prepared your summoning circle accordingly, your hand extended over it as you uttered the incantations, “… Come forth, pass on your judgement, and punish my enemies... Guardian of the Scales!” It lit up with a rainbow light and you shielded your eyes from the brightness.

When you managed to refocus your eyesight, you spotted what looked like a throne of skeletons with a man seated upon it. That wasn’t there before, was it? You glanced down at the three strokes of red etched onto the back of your hand that had appeared as soon as the Heroic Spirit in front of you materialized. He was your Servant.

You looked up at Satoru, but before you could get a word out, he hopped off his seat and circled around you. “You’re my Master? I thought that sorcerers would get stronger with time, not weaker.” He snickered, picking up a pair of sunglasses—Kirei’s—that you hadn’t noticed sitting on a surface and twirling them with his fingers before putting them on.

“Although, if this was your catalyst, I guess you can’t be all that bad,” Satoru smirked, stopping in front of you to finally look at you properly. “We should get the formalities over with. I’m Caster, Gojo Satoru. What grade sorcer-” He lightly traced his fingers along your jaw before firmly gripping it, lifting your face to make you meet his gaze as he corrected himself. “Sorry, you call yourself a mage, right? What’s your rank, Master?”