Clue: Something to excite a fan of necking bad French port (5-4)
Answer: SAINT-MALO
Explanation: Definition: port
A charade of SA (sex appeal, 'something to excite') plus INTMALO, an envelope ('necking') of MAL ('bad') in INTO ('a fan of'). MAL as a prefix is English, leaving 'French' for the definition; or MAL as French for 'bad'.