I am turkish but i think its the same Azerbaijan Turkish. "Bok" means shit, you suffix the noun with vowel i/I/ü/U to express the preposition "to" (the direction preposition). So bok becomes bok+u=boku, literally means "(listen) to shit". So "boku" is not a single word but a preposition plus a noun. Just an extra remark, which of those "i/I/ü/u" will be used as a suffix depends on the vowel used in the last syllable of the main noun. It should follow a certain rule of acoustic. Thats one of the reason Rhyming in turkic languages can be very rich because, the acoustic rules are embedded in the grammar.
Sagopa Kajmer - saldırground its 8 verse oldschool boom bap.its rlly interesting. Whenever the other rappers says to sago "you are not rapper" hes givin a answer everytime. You should react this