Output required for preview??

If I am scripting within a C# component within GH itself, is there a way to have the component preview the geometry without assigning it to an output variable? If this isn't possible through GHs C# node, can it be done through a node developed in Visual Basic? 

The essence of my question is to ask if I can have Grasshopper display a preview of some geometry that is only used as a visual reference for some other related data, something similar to an global axis within any 3d software. What is important is that the axis shows relative direction, not the size of the axis, or color, or shape of the arrows. It just needs to show up.

Preemptive thank you!