Dimensional Sleeve

"Some men use petty tricks to fool their opponents, others don't bother with tricks and just create a pocket dimension to carry that dagger. I mean it's really not that hard." 

-Archmage Kirus

When you use this spell, you may store an item that you can hold weighing up to 15 lbs in a pocket dimension that only you can access. An item that is stored in this manner is preserved as if frozen in time, resuming when pulled out. You may use a bonus action to summon forth the item stored, and if the item summoned forth is a weapon, you gain advantage on the first attack you make with it before the end of your turn. A creature using detect magic is able to sense that you have stored an item with this spell, though they are not able to identify what item it is.