I have a male friend at work, lots of banter (some flirtatious, but I swear only in a jokey way afaic) and good support for each other when chips are down. Have known him a long time and consider him by far my best friend at work, although not a real life friend iyswim. We never meet outside of work. If it seems odd to have a male mate, there are no other women where I work and I have only ever worked with 2 others in the 23 years I've been in the industry.
He was unwell yesterday, so I text him this morning (I'm not in work today) to see how he was. (My mistake perhaps, but you wouldn't think it was odd if he was a female friend) He replied that he was fine, but distracted as he couldn't stop staring at my photo on his desk. He has a group photo from a team event we were all on a while ago. It includes X, a very funny man, who is striking an amusing pose (honest it's really v v funny!) Anyway, I took this to be his usual jokey banter and text back "LOL I thought X was the reason you have that pic" he came back "X makes me laugh, but I'm not madly in love with him"
I nearly dropped the phone from fear and I haven't replied , but I have to go to work (and sit next to him all day) tomorrow