Extract from OED Online

1959 C. MACINNES Absolute Beginners 16 Suze..meets lots of kinky characters..and acts as agent for me getting orders from them for my pornographic photos. 1960 ‘A. BURGESS’ Doctor is Sick xviii. 145 ‘If you think I'm perverted you're completely mistaken. I'm quite normal.’ ‘Normal? You? That's a laugh. You're kinky, the same as what I am.’ 1960 F. NORMAN Fings ain't wot they used t'Be II. i. 52 Fancy anyone being so kinkey about a brown teapot. 1963 Daily Tel. 11 Dec. 19/2 The phrase ‘kinky advert’..meant that she acted as an advertisement for irregular sexual practices. 1964 Ann. Reg. 1963 1 It [sc. 1963] was the year..that women adopted the fashionable long ‘kinky’ boot. 1964 J. BURKE Hard Day's Night i. 11 She was dead kinky for sweetbreads. 1964 Times Lit. Suppl. 8 Oct. 925/1 Zoo men receive a constant stream of kinky letters. 1966 Listener 6 Jan. 23/1 One of the girlsa buxom specimen in kinky patent leathers. 1966 J. PORTER Sour Cream ix. 117 On the one hand I had to trust Zinaida, on the other I knew she was perfectly capable of fabricating the whole scheme just to get rid of Katia whom she loathed. It was like something out of Greek tragedy, only kinkier. 1967 A. DIMENT Dolly Dolly Spy ii. 19 He produced a pack of Black Russian cigarettes, dead kinky, and tossed me one. 1968 [see KINK n.¹ 3c]. 1971 Daily Tel. 16 July 11/4 In a moment of excessively kinky passion a husband strangles his mistress. 1972 F. WARNER Lying Figures III. 36 Kinky sex makes them feel inadequate.