Hi Ryan, I'll repeat myself from my earlier response...
I stated the reason I'd be cautious...because the term carries more significance that just "senior". I happen to train under a Japanese instructor, and from 3rd kyu on our tests are in Japanese. But the terms sempai and kohai are not used. The context for those terms is pretty strongly linked to certain Japanese cultural ideas. They don't always merge well in western social groups (in my opinion). Try a search on some of the abuse issues in Japanese University clubs. I think you'll see what I mean. Especially when linked to deaths in aikido keiko there.
Please note what you said...
This is the same reason I did not accept Ron or your argument that the relationship doesn't exist because you two had never seen it outside of Japan. The real issue I take with Ron's (and your's now) post is that he is making a judgement on a relationship's existance that he knows nothing about in people he knows nothing about.
I never said that in any of my posts. I said that I am cautious about using that term because of the baggage that comes with it outside [and inside] of the Japanese context.
I never made any judgements about whether or not it *could* exist in the specific relationship in question. I simply advised the poster of my own sense of caution.