TouristVisa for Bulgaria to Hongkonh 1 week

Hello ... My friend is from Bulgaria but stay in Berlin ... And he come to visit me in Thailand for his birthday .. We give him a present the trip to Hongkong . We will go to Hongkong for 1 week , do he need to have a visa ... or can he make or arrivel ( tourist ) ... He did ask China embssy in Berlin and they told him that he can make it here .. but I just look that Bulgarin do don´t need visa for 90 days ... thank you for information ... Can he get visa on arrivel ... We did book hotel + ticket alredy ... Thank you so much ...