In tumblr, hashtags can underline the words. It's a way to make the words more prominent. Not here, though.

Tumblr uses hashtags in the bottom of a post to tag it for later search option

Some users use these tags as comments but since they are only on their post and not on the next rebloged one, some people copy tags from other users and post them as a comment for others to see or even use.

Tumblr has a real horrible commenting system and the site feels broken.

I agree. I have a tumblr because of a girl I like and I have just found it absolutely terrible to use. I have trouble seeing comments and searching stuff seems a bit clunky. In all it seems clunky and just neglected to be fixed. I mean when I go to see comments all I see is the people who reblogged it. I dont know how people can get comments like above. I am just really confused by the layout. Maybe I should ask her how to use tumblr.

Have a unrelated video simply because I feel the need to upload something with my comments.

#S#o#u#n#d#s# #g#o#o#d

It's weird. My PC-98 emulator actually displays text like that.