It does seem to be flowing around the hand at this moment. The image itself is a rectagle so you'd have to break the text into multiple elements and position them as best as you can to mimic flowing around a non-rectangle object.
If I'm understanding you correctly, then yes, you would need to follow JorgeM's instructions. Keep in mind that for most intents and purposes, elements in a browser are all rectangles! Your image takes up a full rectengle, even if it doesn't look like there's anything in the bottom-right corner. So the text will float along the straight edge of the box.
If you want the text to look like it's fitting the contour of the hand in the image, you'll need to position the text accordingly manually. There are a number of ways to do this. You can use a graphics program to type the text into the image, but then this text can't change without changing the whole picture, and you lose the SEO value of the content. Another option is to use absolute positioning to place the text just so, but you'll need to fiddle around with this manually.
Honestly making the text part of the image is probably your best and easiest bet.
This VB.NET imaging control library does not just allow you to draw text on images, it also offers flexible settings for you to adjust the text properties, such as font type, font size, font style, and brush color, etc. After all the editing, you can directly save the images to your local files for future processing.