I'm very tempted to get this, but considering I just got the Humble Indie Bundle 6 when it came out and RollerCoaster Tycoon from the weekend sale, I'm kind of hesitant to get anymore games in the near future.

I dabbled around a bit with "Spirited Heart Deluxe", the bonus game that was unlocked after 1000 sales. On the "relations" page, it mentions something about "limited romance options until you buy 'Spirited Heart Love'".

Am I doing something wrong, or did Winter Wolves have the audacity of rewarding their customers with an incomplete game?

That seems to be the case; there was the game, then the expansion "Girl's Love," and the expansion is not included with the bundle. But it's OK, you can buy it separately! For ... twenty dollars? Fuck's sake, Winter Wolf.

i guess thats why it was a bonus game, still not cool though

Heileen & Heileen 2: Steam keys have been added.