Can I submit a request for a pre-order item and make an order Pre-order ?

Sure, we can accept requests for pre-order items!
We require payment upfront for all pre-orders. When you place the order with us we will review the order and then charge you at that time. We can not charge for pre-orders when they release, only when the order is made with us.
As for the cancellations for your pre-order on the store we purchase from, most Korean stores do not accept cancellations so therefore we also can not cancel pre-orders once we have ordered from the shop.
If the shop does accept cancellations then we can cancel an order made with us as well.