My wife's sister keeps expressing the thick sperm she's stored up for pregnancy, which is why my wife has difficulty conceiving... (YUJ-036)

My wife won't have sex with me unless we want to get pregnant. On the other hand, my sex drive is very strong; I won't feel satisfied unless I ejaculate every day. My OB-GYN even told me to abstain from sex, otherwise my sperm count will be very low. I try my best to abstain, but every weekend my wife's sister comes to my house and drains all the sperm I've accumulated...