I think here means something like "for fun" or "for leisure". In other words, they came on a pleasure trip, not for business or studying.
What may be confusing is that it's natural to express this in Japanese directly when you'd express it only indirectly in English. Phrases like "came to visit" or "went to see" generally _imply_ that it's for pleasure and not for business. You don't need to say "My friend came to visit me **for pleasure** " because it's implied by the phrase "came to visit".
As a result, the most natural translation here doesn't include words like "for pleasure":
> [ **** ]
>
> [ my friend who **came to visit** from Japan ]
But it's natural to express it explicitly in Japanese with . Phrases like and are very common.