Can I get liposuction to remove the side boob without a breast reduction?

I think what you are describing are called axillary rolls that can be targeted successfully with liposcution.  This will improve the contour but will not affect the breast.

Certainly you can.  Generally this area responds well to liposuction.  If you have extremely lax skin then you may not have the best results.  When you talk to your surgeon make sure you carefully discuss and are clear about what areas will be treated.  Be prepared for some swelling and recovery time until the skin retracts completely.  Best of luck!