A tale of the Quaranteam world, original by CorruptingPower

Adam Jeffries tried to do his best in the face of two separate plagues sweeping the world, able to kill fully 25% of women who contract it and over 80% of men. It wasn't enough. Following a break-in he finds that he has contracted it... when he wakes up in the hospital, apparently a rare male survivor. Now the government, seemingly by way of apology, is making sure he gets his vaccine serum in order to make sure he doesn't have to go a second time around. The serum, however, kills men even faster than the disease. The solution? Make it sexually transmitted, and assign remaining men partners according to a compatibility engine called Oracle.

There were... side effects.

Some were known. The women experience a sharp spike in libido and amazingly powerful orgasms, and become bonded to their partner for life. Others were not so common. Some people experience a rapid healing, though not all. The members of Team Jeffries seem to have a unique reaction to the bonding, transforming over time and much more. Where it stops, nobody knows... but the same forces behind the project of saving humanity seem to have taken an interest. Adam? He just wants to live. Is that too much to ask?