Assassin is quiet and composed, and while his general tone has a mocking nature to it, he takes it to another level with Caster. He is honorable in battle, always maintaining a degree of bushido, and he is not the type who would attack defenseless women and children. He willingly keeps Saber from exposing her name without any ulterior motives, and he prematurely stops their fight to keep an opponent from spying on her Noble Phantasm and possibly going after the weakened winner of the battle. He has no actual goal in participating in the Holy Grail War. He is not a Heroic Spirit, so there is no advantage to winning for him. He reveals his "true name" without regard, and seems disinterested in Caster's promised reward of making him into a real Sasaki. He only guards the gate while eagerly awaiting Servants to battle.