"You're loyal" is an English equivalent of the Italian phrase Sei fida. The present indicative in the second person informal singular and the feminine singular adjective also may be translated into English as "You're devoted" and "You're faithful" according to context. The pronunciation will be "SEH-ee FEE-da" in Italian.
Chi sei? in Italian is "Who are you?" in English.
Sei bravo! in Italian means "You're good" in English.
Sei bella! in Italian means "You're beautiful!" in English.
"Six" in English is sei in Italian.
sei li?
Perché sei arrabbiato? in Italian means "Why are you angry?" in English.
Tigrotta sei! in Italian means "You're a little tiger!" in English.
"You are special!" in English is Sei speciale! in Italian.
"You are horny!" in English is Sei arrapato! in Italian.
"Are you safe?" in English is Sei salvo? in Italian.
"You're in charge!" in English is Sei in carica! or Sei responsabile per...! in Italian.
Sei un cavallo! in Italian means "You're a horse!" in English.