I'm not sure if you'd want to read this but most of the settings are about them in a cafe, although it's BL, it's quite popular so I wouldn't be surprised if you have read it but it's called 'Sign'
Affectionately
Maybe these:
http://www.mangago.me/read-manga/kowagaranai_de_soba_ni_ite/
http://www.mangago.me/read-manga/sore_wa_are_da_ai_kamo_ne/
http://www.mangago.me/read-manga/hatsukoi_no_atosaki/
http://www.mangago.me/read-manga/hoshi_dake_ga_shitteru/
http://www.mangago.me/read-manga/soshite_boku_wa_koi_wo_shiru/
http://www.mangago.me/read-manga/nekasenaide/
Any straight or yaoi where it’s in a cafe setting; they might be coworkers or met each other in a cafe