hot and heavy
Very enthusiastic and excited, as in That was a hot and heavy debate. This slangy expression employs hot in the sense of "characterized by intense feeling," a usage dating from the tenth century a.d., and heavy in the sense of "serious."
Passionate, lustful, as in They were awfully young to be so hot and heavy about their romance. This slangy term employs hot in the sense of "sexually aroused," a usage dating from about 1500.