My BF gives me money based on the rounds of sex we have

From a female CFB reader...

"I sometimes spend the weekend at my boyfriend's place. He deflowered me and I don't have any regret but I suddenly began to realize that he grumbles whenever I visit him during my menstruation. He would reluctantly give me 1k for transport. Another thing I observed is that he gives me money based on the rounds of sex he has with me. Let's assume we had sex 5 times, he would give me 5k for transport and on the day or weekend we have it 3 times he would give me 3k. Is this normal or its just a way of paying 1k for each round of sex?