NOTE: I thought it was obvious, me being a Pirate and whatnot, but this post is about Low Sec.
There is no such thing as a "Blob" in Eve Online. It doesn't exist. What does exist is players with friends who like to fly together in small gangs, or black ops fleets, or operations that require more than just a few players. The range of reasons why more than one person might be flying together is immense. So I won't bother trying to list them all. Let's just agree that people tend to fly together in Eve Online. It is, after all, the entire reason the game exists - from Corporations to Alliances - getting people to fly together is the entire point. Eve is not promoted, constructed, or expecting us to fly around all by ourselves. That's just weird.
You choosing not to participate in that scheme is your own deal. Not theirs. When I choose to fly solo it's for a reason. I much prefer to fly with a handful of other pilots, small gang is what I enjoy most about Eve. But that isn't always possible, again for a wide variety of reasons, and I also enjoy flying solo. But that is my choice. My choice has zero bearing on the vast majority of other players who are not flying solo. So when I bump into those players, it would be weird for me to complain about it. My job as a solo pilot is to avoid those situations and try to optimize my own opportunities for success. Bumping my ship into a fleet or a gate camp is a failure on my part. Not on those enjoying those activities.
Now that we've established some ground rules, let's talk about intent.
Scenario One: There is this pilot in a nearby system that typically flies a Worm or a Comet and he hangs out in a faction plex. Normally this would be a great situation for a solo pilot to happen upon. Both are tough ships to slide into, but that is the entire point. We like challenges. The thing is however that this pilot always has another pilot on stand-by somewhere in system who, once you engage, will come to his aid. This tips an already close fight into one he will win. Is this a blob?
Scenario Two: There are two other ships in local, one in a small and one in a novice. They are probably together since they are not currently fighting each other. If I attack one of them and the other comes to assist, is that a blob?
Scenario Three: There are four Kestrels in a small plex. I choose to engage them in my Assault Frigate, because that is what I happen to be flying. Normally this 4v1 would be considered a good fight, from my own perspective. But I also know I will most likely slaughter these pilots. And I do. Even though they outnumbered me, did I just blob them with one ship?
I could go on and on. Blobbing is in the eye of the victim. While I believe that actual/real/true BLOBS are so rare as to be non-existent - I also know that they can happen in certain very special circumstances. Because we've all done them. There have been times when I could probably kill something with what I have on hand, myself or a few others already in fleet with me, but yet the kill is so tasty that I call on others to come join the fun. Even though they aren't needed to secure the win. It's rare, like I said, but let's not pretend it doesn't happen. And I've been on the other side of that equation as well.
Which is a lot of words to say this truth - it all comes down to intent. We all want to win. Losing sucks. And often we will do whatever it takes to win. And when that "whatever it takes" is used against us, it can feel really horrible. It can feel like you just got blobbed. It's no fun. When it happens to me I get my Pod out and re-ship and continue on with what I was doing. I always remember that next time it might be me and my friends pilling onto that Porpoise I tackled in a belt.
A blob is just a bunch of friends flying together, hoping they don't get blobbed. Because there is always a bigger fish out there. And some days that bigger fish just happens to be you.
And sometimes it isn't.