Active type, welcoming party, flipping left: he seems bored (7)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

DOER(an active type/a go-getter) containing ( welcoming ) [ reversal of ( …, flipping ) DO(a party/a social function) + L(abbrev. for “left”) ]. Defn: He whose boredom is signalled by drawing absent-mindedly.