To be honest I think you should spill the beans. I've never heard someone say "It's 'other half day'"

Obviously (Well maybe) he likes you in some way. I don't know, stay calm about it, it's other half day.. So it has to be you and him and it does sound rather unusual. Sounds like he may be hinting or hoping for something; though don't get your hopes up, I may be wrong.

OH! And stay clam! M'kay? Also if you really like him maybe you should give him a hint or something. I have this phrase..

Unspoken words.. Excuse the font, it's off some profile I've seen but I like to use the phrase..

ιf унσσ ℓσνє ѕσмєσиє тєℓℓ тнєм, вє¢αυѕє нєαятѕ αяє σfтєи вяσкєи ву ωσя∂ѕ ℓєfт υиѕρσкєи =[

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