Green’s Dictionary of Slang

1. something or someone luscious, i.e. sexually titillating.

1878		‘’Arry on ’Igh Life’ in Punch 20 July 24: You will find it [i.e. a news report] a proper old lush, / [...] it might make a mealy one blush.
2017		theculturetrip.com ‘Guide to London Slang 10 Jan. 🌐 Lush – good-looking bloke or gal you want to have sex with.

2. (US gay) an extremely attractive heterosexual man.

1949

‘Swasarnt Nerf’ et al. Gay Girl’s Guide 12: lush: NYC MBS [Male Bobby-Soxer] term for a terribly attractive but incorrigably heterosexual young man.