Man, trying to get Yumiko's Easter Egg is proving really tricky for me.
I'm following the Guide & got the direction perfect on the first, but it doesn't seem to matter how far I go over the green for the 2nd two, it always lands in exactly the same place, [SPOILER="right between her tits on the bar"
If you think of each of the 3 elements of the quarter shot (dir, depth, force) as a number between 1 and 100, and the green flash for each of the 3 gives you a value of 50...
What you want is direction = 50 (green flash), and depth force combined have to add to between 130 and 150. Can be hard to get depth, force just right as you've discovered...
What worked for me was clicking green for both direction and depth but then going for absolute max force (so when the finger in the animation is curled back as much as possible.) So that would be dir=50, depth = about 50, force = about 100.
To top it off, there's a random element here...even if you get the numbers right, RNG will only give you the easter egg 1/3 of the time. (I had a peek at the game code.

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