Roche was born to the house of Frain under Yggdmillennia. Well known in the field of doll engineering, he was raised like all other members of his house, nursed by golems from the moment of birth until reaching the age where the crest could be passed on to him. He had been completely raised by the golems because his parents rarely left the workshop to see him, so they took care of even his education. This caused him to become very familiar with them and develop his eccentric personality. He became famous in his field even at the age of thirteen.
He became a Master, the youngest of them, and summoned his Servant, Caster of Black two months before the Great War. They spent the majority of time in Caster's workshop creating golems for Yggdmillennia's war force.
Roche is much like the other members of his house in that working with golems and seeing the habits, their acts and speech from their human-based forms and the way they continue to work day and night, he has taken that as his common sense. Golems have become the norm instead of humans within his eccentric upbringing, so he will remember the face of every golem that has cared for him even if he may have forgotten his parents' faces. He has no interests in humans or even other magi. While he can exchange words with others, allowing for dealings in bidding wars to secure resources, he does not display the cordiality normally found in dealing with humans or magi. He compares it to how a man speaking to a dog or cat can hardly be said to be bonding in heart or mind.
The only exception is his respect for Caster, calling him master (先生, sensei) instead of addressing him as a Servant. While Caster is not a king that one would normally treat as such to appease their dignity, Caster's achievements in his field are more than enough for Roche to treat him as such. Caster is an ideal teacher, and they spend all of their time on his creations. Caster's legends are worthy of worship to him, so he has every trust in his Servant and feels genuine happiness while helping him.
Roche is obsessed with his practice, so he spends all his time in his workshop in the castle. It is rare for him to leave for anything, but notes that something like witnessing a once in a lifetime event like a Servant summoning even for the second time is well worth it. He attempts to sound adult when speaking, but tends to overdo it.
Yo, thanks for acceptin' the request I sent. I'm Shura Kirigakure an Exorcist and on some days even a teacher I suppose. I don't really like making these things long so skipping to the good parts---I gotta be honest and say I'm new to the Fate series. Only just recent started watching it, but I am interested in the series and it's characters. I'd love for the chance to get to learn more about it through some interactions with those of you in the verse so if you ever wanna get a story going don't hesitate to let me know. I'm also usually friendly so chatting is more than welcome and you're free to contact me through comments or messages whenever you'd like.