JedA1 has the straight poop. If the wings are level and the ball is centered, the pilot is not subject to funny forces, but the vibration environment, especially at the low frequencies (4 to 7 Hz) can be a real back issue. Typical 2 bladed Bell 1/r and 2/r is a major problem for back and kidney problems, at least in the 212 world. The 412 and the 430 are quite nice on vibes, however.
The helicopter naturally flys crooked in cruise while wings level and ball centered, typically for low speed machines it is about 5 degrees of left nose, right sideslip in cruise. As the speed goes above 130 knots, the sideslip gets to within 1 degree or so. This sideslip feels like a cross wind, and is compensated the same way, fly toward the right window frame, navigate like a 10 knot left crosswind is always there.
This slip is needed to produce a fuselage side force that balances tail rotor (and vertical fin) anti-torque force.