Lakshmi:
If she is standing on a bed, could we not tell her approximate location based on the imprint of her weight on it?
Yeah. Good and fair point. Let's assume the bed impression allows one to attack her at -4 to hit, per normal attacking in darkness/invisible rules.
I guess the rope would be visible now:
Invisibility
Level: 2
Duration: See below
Range: Touch
The creature or object touched becomes invisible, vanishing
from sight, even from infravision. If the recipient is a creature
carrying gear, that vanishes, too. If the spell is cast on
someone else, neither the caster nor any allies can see the
subject, unless they can normally see invisible things or other
magic is employed to do so.
Items dropped or put down by an
invisible creature become visible; items picked up disappear if
tucked into the clothing or pouches worn by the creature.
Light, however, never becomes invisible, although a source of
light can become so (thus, the effect is that of a light with no
visible source). Any part of an item that the subject carries but
that extends more than 10 feet from it becomes visible.
Of course, the subject is not magically silenced, and certain
other conditions can render the recipient detectable (such as
stepping in a puddle). The spell ends if the subject attacks any
creature, but is otherwise of indefinite duration. For the
purposes of this spell, an attack includes any spell targeting a
foe or whose area of effect includes a foe. (Exactly who is a
foe depends on the invisible characterÊs perceptions.) Actions
directed at unattended objects do not break the spell. Causing
harm indirectly is not an attack. Thus, an invisible being can
open doors, talk, eat, climb stairs, summon monsters and
have them attack, cut the ropes holding a rope bridge while
enemies are on the bridge, remotely trigger traps, open a
portcullis to release attack dogs, and so forth. If the subject
attacks directly, however, it immediately becomes visible along
with all its gear. Spells such as bless that specifically affect
allies but not foes are not attacks for this purpose, even when
they include foes in their area.