a su asesino

his/her killer

→ a
phrase Rare #47,419
his/her killer The initial “a” is often the personal a, used before a person who is a direct object, so it isn’t translated into English. Depending on the verb, the phrase can also mean “to his/her killer.” “Su” can also mean “your” or “their.”
SP: La policía encontró a su asesino.
EN: The police found his killer.

O quizás vigilaba a Johanna y no a su asesino.

Or perhaps he was keeping an eye on Johanna, not her killer.

— Legado en los huesos (2019)

Pero he encontrado a su asesino.

But I have found his killer.

— हैदर (2014)

Ellos siguieron tu ejemplo y perdonaron a su asesino.

They followed your example and forgave their murderer.

— El Auto De La Compadecida (2000)

Sí, la víctima le regaló la corbata a su asesino.

Yes, the victim gave the tie to their killer as a gift.

— Indagine su un cittadino al di sopra di ogni sospetto (1970)

O sea que la víctima le regaló la corbata a su asesino.

So the victim gave his tie to his killer.

— Indagine su un cittadino al di sopra di ogni sospetto (1970)