Astolfo is a Servant from Fate/Grand Order and Fate/Apocrypha and the Twelfth Paladin of Charlemagne.
Astolfo is the Rider-class Servant of Celenike Icecolle Yggdmillennia as part of the Black Faction in the Turifas Holy Grail War of Fate/Apocrypha. After the death of Celenike, he forms a contract with Sieg.
He is one of the Servants of Ritsuka Fujimaru of the Grand Order conflicts of Fate/Grand Order.
“Oh, I would definitely suggest against leaving it entirely for me to decide. For no man can show as much a lack of restraint as I, Astolfo!”
—Astolfo speaking to Sieg
Astolfo is known in his legend for being eternally optimistic and completely lacking in sense, and he can be called "curiosity in human form". As a Servant more concerned with the current prospect of a second life over all else, he is one who will, with or without permission from his Master, instantly leave when not in conflict to indulge in the pleasures of the world. He greatly enjoys physical form rather than the usual practice of being kept in spirit form except for battle, and obtaining permission to do so is enough to cause him to dance for joy. He is a frightfully unparalleled blabbermouth, prone to speaking on and on until those involved lose all rationality. His conversations, through no ill intent on his part, have a way of meandering toward maximum social awkwardness. His hobby of adventuring gets himself mixed up in an assorted amount of mischief due to him constantly popping up everywhere. Since he has no wish in special to entrust the Holy Grail, this Servant's motivation greatly fluctuates depending on whether or not he likes his Master. The type who is frankly straight with the person he came to like, regardless of the said person being of the opposite or the same sex.
Astolfo leaves all hard decisions as a matter for his heart to decide on the spot, following the course he deems most fit. He does as he pleases without regret, and such obviousness of course would be hard to fathom from anyone other than him. He decides to save Sieg entirely on such a pretense, and not knowing how far he will be able to help, simply states "I'll keep helping him until I stop".
Rider took it upon himself to help Sieg when they first met simply because he wanted to. He promised to look after Sieg until he had been wholly satisfied, even after being told that Sieg would live for three years due to being a homunculus. Rider would later help Sieg escape from the Yggdmillennia despite knowing the retribution he would receive from the rest of the Black Fact for this treacherous act. He is able to inspire Sieg to continue living even when the latter thought it to be pointless.
Astolfo is an androgynous-looking boy who is fancily dressed. Beautiful beyond all compare, he states that his hair ornaments, which seem like something a princess would wear, are an "irresistible proof of friendship" that he uses to restore peace to his cousin, Roland. His appearance is contrary to the legend of being said to be the most handsome among the Twelve Peers of Charlemagne, and though extremely unexpected, it is natural for legends to become distorted. He purposefully dresses as a girl because he likes cute things. His gender in the servant status was written "le Secret♪".