Moving in with your datefriend because you’ve fallen deeply for them and they’ve fallen deeply for you.
Your first romantic date consists of a nice cut of steak, potatoes, greens, and red wine.
for them.
Because you’re under the [rather large] table enjoying your meal straight from the tap.

Not noticing your actual food intake going down over the next years, until you realize one day that you’ve been consuming nothing but your partner’s cum for a week straight.

Breaking down one night and telling your partner that all you want to consume is their spunk. That you didn’t ever imagine yourself that hooked on cum, but you are and you don’t want to stop.
They hold you, comfort you, giggle, and assure you that they have known for quite a long time.
And if you want, you can always have as much as you’d like.

Settling into you’re wonderfully strange diet and having a number of months to a year of pleasantness before your physique starts to change. At first, it’s a bit of chubbiness, but you like that and all things seem healthy. Your datefriend teases you about it every so often and it feels nice.

doing a lot of physical activity at work one day about a year in and catch yourself feeling particularly slick. You curiously taste your sweat and are alarmed at the taste.
Maybe this diet is having unintended affects but…
Well, you aren’t stopping of course

Taking more and more time working at home because you keep sweating spunk. It’s getting worse, but you keep your diet strong. Not that you even want stop now. You don’t hide it from your datefriend and they encourage you as long as you are happy.
Which you are, even as your skin starts to oddly shed

Becoming more and more settled into your life as a living spunk creature, your lust sparking your brain in great betrayal of your humanity. Your datefriend doesn’t mind, as long as you’re happy. It is a positive that you can take their entire house-shuddering orgasms now.

In closing: i really like cum???

@Oneironott Nah, I don't believe it. :P