"He no longer wants to be here."
Translation:On už tady nechce být.
It is not clitic. It just prefers the second position when it is not in the first or the final position. But it certainly can be first or last. Especially when the "here" is the new bit brought by the sentence, the thing you are actually conveying, it can be last. He no longer wants to be here. He want's to be at ... Už nechce být tady. Chce být v ... The pronunciation must be adjusted to the appropriate intonation stressing the final word in such a case.
Please note that we have only a single report requesting the word order you are asking about and it is very old. I will add it now.
On is not essential at all.