There's these bugs that were crowding around my tomatoes and I don't know what they are. I flipped a nearby leaf over and discovered a cluster of eggs and realised that perhaps the bugs were guarding the eggs. What is this bug? Is it a pest?

@Melanieqin It is difficult to tell from the image you posted. I tried blowing it up, and it looks like a lady bug to me. The ladybug, commonly called the Asian lady beetle is a pest as well as a beneficial insect. They are really only a pest by their presence. Ladybugs do not feed on or damage anything in the home.

Can you get a closer image of the bug?

Looks like the Asian Ladybug to me as well......where are you growing the tomatoes this time of year?