Re: Item build for Demon witch(Lion)
Any build which costs more then 4k gold, is unrealistic.
Lion shouldn't be farming much at all, game plan's to keep pressure on the enemy team, and gank, gank and gank.
I'd favour roaming from level 6, since finger's just sweet, but you should gank earlier, if any opportunity arises.
Magic Wand + Bottle + Boots is more then enough to support your ganking needs.
Ward if your team requires a warder, and never ks unless necessary, giving your teammates the gold instead, since you don't need gold much.
Possible item choices are Dagger, for mobility, but most will prefer the Guinsoo's, since hex is just that awesome.
Necrobook and Eul's are considerable as well.
But, of course, other then your Bottle + Magic Wand + Boots + Point Booster , the rest are all luxury.