to miss the 1st flight, don't show up....then dont show up for the 2nd, because it will be canceled when you miss the 1st....

the? has been asked before, & the answer hasn't changed....

i'll give long odds that you have a ticket from a-b-c then c-b-a which was cheaper than b-c-b.....

so, figure how to get to a...then, as you said, just get off at b on the return....

checking bags would require a short check on the return...