For a while, it was this sleepy little happening on campus, but within the last 18 months, we've seen much more interest on the part of publishers

What does "this sleepy" mean?

We all know that "in" is usually used after "interest". Can anyone tell me why "on" is used in this sentence?

1-- Sleepy in this kind of situation usually means inactive; quiet: a sleepy rural town. (courtesy of American Heritage Dict.)

2-- on the part of is a complex preposition. It is not collocated with interest. There has been an effort on the part of the management to limit overtime.
We don't know what "it" refers to because it refers to something outside the given sentence. We need more sentences from the text in order to know what "it" is.

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What does "it" refer to, the it that is sleepy?
 CalifJim's reply was promoted to an answer.
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