Women's breasts can be modeled as a cone and measured as V = (Db^2*h*.785)/3 and since breasts can be thought of as an amorphous fluid, you just have to worry about containing the volume of the breast.
Because many mages regard Improved Arcane Explosion as necessary, it would be preferred if it was simply made into an instant-cast spell available through training alone and not through talent point expenditure. The same sentiment applies to Evocation. wtf