<s>
Signal	O
(	O
stylized	O
as	O
SIGNAL	O
)	O
is	O
an	O
otome	B-Application
game	I-Application
released	O
on	O
December	O
3	O
,	O
2009	O
by	O
D3	O
Publisher	O
for	O
Nintendo	B-Device
DS	I-Device
,	O
in	O
both	O
a	O
standard	O
and	O
a	O
limited	O
edition	O
.	O
</s>
<s>
It	O
is	O
part	O
of	O
a	O
series	O
including	O
the	O
PlayStation	B-Device
2	I-Device
game	O
,	O
sequel	O
to	O
the	O
PC	O
game	O
Darling	O
.	O
</s>
