As stated prior, upgrading the Computer decoration to level 5 opens Diamonds as an option in stock market.
After 5 it's useless to max it to 6 for anything but the aesthetic if you really want it.
Anyone know the max level for each Prestige?
The max level you can hit easily enough is based off your decorations so... ( >.>);
In case the multipliers matter for anyone's decision on the event girls, Victoria the vampire has small breasts, small feet and medium height.
Sacred Sword Princesses invite code for server 2: Ruu0006963
If that's the case, sounds like the succubus is the closest match to Ingrids boosts if I'm not mistaken ( o.o)