[Rin grunts and makes a show of looking exasperated, shaking her head. When she starts to speak again, it sounds like a lecture.]

Look, I'm not blaming you since it was your first time [or so she assumes, anyway], but... Throwing yourself on a sword for someone sounds well and good in theory, but in practice, it means the best case scenario is one person escaping. Worst case, you don't buy them enough time and there are two bodies instead of one. It's much safer and more effective if you do something to disable the attacker instead.