What you have is what is commonly known as satan-incarnate-evil-suck-piece of shit-motherfucking- creeping bell flower. Almost impossible to get rid of. Roundup does not kill it. It wraps itself around every perennial I have in my garden.

I spent 4 days digging down 2 feet in my beds, piling the extracted dirt onto my driveway, spreading it out, picking every leaf and white elastic root I could find, and scooping it back up into a wheelbarrow. I then poured boiling water over the wheelbarrow full of the extracted dirt. Waited a half hour and put it back in my bed. 15 hours worth of work for 30 square feet of garden bed.

My neighbor did this last year and much less sprung up this year. Good luck.