Let me start this off with a warning. I am an obsessive Integra fangirl. While there's a place in my heart for every Hellsing character, Integra is the one who's captured it whole. If this profile/shrine/site does not bowl you over with the sheer awesomeness that is Integra, the fault is mine, not hers.
Integral Wingates Hellsing is the leader of the Hellsing organization, having inherited that position in a direct line from Professor Abraham Van Helsing. She's the last of the family; luckily, she's perfect for the job.
She's a Knight of the Round Table, complete with sword. She holds the rank of Brigadier in the British Army, and has a spiffy uniform to go with the title, though she doesn't wear it much.
She's easily mistaken for a bishōnen at first, considering that she wears men's suits and is addressed as "Sir Integra" (refer back to the bit about being a knight).
She takes no nonsense from anyone, accepts no failure, tolerates no stupidity, loses no control (well, most of the time), takes no prisoners, and shows no fear.
She is incredibly, incredibly hot.
She inspires devotion in her allies, fear in her enemies (the wise ones, at least), and respect in everyone. Because she's that awesome.