This t-shirt design is for the Barbican's current film season - Cinema's Baddest Girl Gangs.
Stray Cat Rock: Sex Hunter is a Japanese exploitation film made in 1970, starring Meiko Kaji.
The Barbican has a wonderfully spot-on description of it here. (Truly, the best hat in cinema history)
WeAdmire have a pop-up shop in the foyer of the Barbican where you can purchase the t-shirts.
(They are also available online here.)
I personally loved the film - it's fun and swaggering, the ending is genuinely quite perplexing, the ratio changes for no particular reason in certain scenes, coca-cola bottles are used as molotov cocktails, Meiko Kaji is amazing as Mako right from the start (- that hat!)...all best seen on the big screen. Also, as far as I can tell, it isn't available on Region 2 (though it appears Arrow Films will be releasing a box set of the Stray Cat Rock films later this year, which is really promising)
(Barbican Podcast on Cinema's Baddest Girl Gangs)