Sorry to read that you're so frustrated. Maybe drop rates were too low. Maybe not, thousands of players managed to get the girl.
But as a general thinking line, I would not see the fun in having girls "guaranteed".
Obviously you're not going to like this, but playing a game implies that you have chances to win... or lose. If you win no matter what, it's not a game anymore.
If you know games that do it better, give exemples and we'll try them. And if we see convincing mechanics, maybe they'll inspire us for upcoming events... yes there will be a big "Christmas" event

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