Chinese Clematis (Clematis orientalis) only wraps itself around other plants. It doesn't suck their juices. However, it can be harmful to the plants it climbs over. It will compete with them for sunlight, much like if you covered them with cloth. Where the clematis stem wraps around the other plant stem, the other stem won't be able to grow any larger, just like if you tied string around that plant stem.
Some plants will not grow as fast as the clematis, and will end up dying or being stunted because they don't get enough sunlight. Some plants will have stems that get strangled and split open, leaving them vulnerable to diseases through the open wound. Other plants will cope with the competition for sunlight and the stem wrapping, and do just fine. It depends on the plant and how healthy it already is.
It looks like you have some tomatoes in the background. I would make sure the clematis stays off of the tomatoes. At best it would reduce your crop yield. At worst it might kill the tomato plant.
It's worth noting that Chinese clematis is classified as a noxious weed in some places. That usually means it will be a problem plant in your garden. Probably best to get rid of this one before it spreads. It's also possible the app mis-identified the species; you may actually have Clematis terniflora. That one's invasive, and (in my personal experience) basically impossible to get rid of once it's established. The fact that it "volunteered" to grow in your garden is a sign that it might just "volunteer" to grow everywhere in your garden if you let it.