"Boss, can I get a day off? I'm sick today."
"No problem, you will make it up when you feel better. Is it something serious and will you be gone for a longer period?", the boss asked.
"I'll be coming in tomorrow, don't worry" John replied."Great, I will see you tomorrow then."
Then it was Tuesday. John came to job, in perfect health, thanked the boss for the day off and was working as usual. So the week passed, then the weekend and it was already next Monday.
"Boss, I'm sorry to call you again, but can I get this Monday off as well? I'm sick."
A bit weird, two Mondays in a row, but what can you do, the boss thought. It's just a coincidence.
"Sure, no problem. You'll make it up when you're feeling better", the boss replied.
And so came Tuesday. Boss was worried about John, but didn't want to pry, so he let it slide. John worked as usual that time, and for the rest of the week.
Then, the next Monday arrived.
"Boss, I'm really sorry, but can I have this Monday off as well?" John asked.
Boss knew something was off, but better not to have John around sick he though, if he was even really sick, so he decided to talk in private, after John was feeling better.
"Ok John", the boss replied. "This is getting weird but you just rest, you can't function while you're sick. I suppose I'll see you tomorrow?".
"Yes, I'll be coming tomorrow as usual.
John was at work the next day so boss decided to find out what was going on.
"John, we need to talk. One Monday is not a problem, two Mondays in a row are a bit weird but things happen, but three Mondays are no coincidence. What is happening? I need an explanation." The boss was not happy at all.
John decided to be honest. "Well, here is the thing. Every Monday, before work, I go to my cousin for a cup of tea. Every time we start drinking tea, chatting, and we always end up having sex."
"Oh my god! Sex, with your cousin? You're sick!"
"Well I told you so!"
Sorry if I misspelled something, heard the joke it in my native language.