hmmm, to me a kiss should b open mouth
Cuz if u pucker up, ur lips will b very tight and it is a BIG TURN OFF of the romantic moment. Just relax and let ur emotion talk over
and btw, do not try to open ur mouth too big and slobber all over her mouth/lips/chin with saliva.
p/s> u can always just lick around and explore other's mouth n teeth ^^